Common Linux Terms
Account Name Same as Login ID, User ID, or Username.
The name assigned to a user on a Linux system. Multiple users can be set up on a system with unique account names, each with varying access (permission) levels. After Linux installation, account names are assigned by the Superuser, or root operator.
ACPI (Advanced Configuration and Power Interface)
The Advanced Configuration and Power Interface provides power management functionality on x86-based platforms.
ALSA (Advanced Linux Sound Architecture)
A framework for accessing sound cards and other audio devices under Linux. ALSA includes support for most popular audio chips and adapters. ALSA has replaced OSS on most distributions. (Also, see OSS.)
APM (Advanced Power Management™)
An industry standard for allowing the system processor and various components to enter power-saving modes, including suspend, sleep, and off. APM software is especially important for mobile devices, because it saves battery power.
A single large file containing multiple files, usually compressed to save storage space. Often created to facilitate transferring between computers. Popular archival formats include arj, tar, and zip.
Awk (Aho, Weinberger, and Kernighan)
A programming language useful for its pattern matching syntax, and often used for data retrieval and data transformation. A GNU version is called Gawk.
A program that is running without user input. A number of background processes can be running on a multitasking operating system, such as Linux, while the user is interacting with the foreground process (for example, data entry). Some background processes-daemons, for example-never require user input. Others are merely in the background temporarily while the user is busy with the program presently running in the foreground.
Bash (Bourne Again SHell)
An enhanced version of the Bourne Shell. (Also, see Korn Shell.)
A variety of bitmapped fonts for the X Window System. (Also, see PostScript Fonts and TrueType Fonts.)
A directory containing executable programs, primarily binary files.
Source code that has been compiled into executable programs. In the Linux world, some software is distributed as source code only; other packages include both source and binaries; still others are distributed only in binary format.
A disk (floppy or CD) containing enough of an operating system (such as Linux) to boot up (start) the computer and run some essential programs from the command line. This might be necessary if the system was rendered non-bootable for some reason. A boot disk can be used to partition and format the hard drive, restore the Master Boot Record, or copy specific files, among other things.
An application that handles the initial startup of the computer. Bootloaders set up the initial environment, and then hand off the process to the selected operating system. (Also, see GRUB and LILO.)
Short for Robot. A program designed to search for information about the Internet with little human intervention.
A popular command line shell offering many advantages over the DOS command prompt. (Also, see Bash and Korn Shell.)
BSD (Berkeley Software Distribution) UNIX
UNIX distribution from University of California at Berkeley. (Also, see FreeBSD.)
A newer file compression program for Linux, providing smaller file sizes than Gzip. The file extension is usually .bz2.
CGI (Common Gateway Interface)
Used on Web servers to transmit data between scripts or applications and then return the data to the Web page or browser. CGI scripts are often created using the Perl language and can generate dynamic Web content (including e-commerce shopping baskets, discussion groups, and survey forms).
Disk information required by FDISK during partitioning.
A machine that requests services (e-mail, for example) from a server.
A network of workstations (PCs or other) running Linux. (Also, see Beowulf.)
Command Line Interface (CLI)
A full-screen or windowed text-mode session where the user executes programs by typing commands with or without parameters. The CLI displays output text from the operating system or program and provides a command prompt for user input.
The DOS, Windows, and OS/2® term for the part of the command line interface where the user types commands. (Also, see Shell Prompt.)
To turn programming source code into an executable program.
A language that requires a compiler program to turn programming source code into an executable machine-language binary program. After compiling once, the program can continue to be run from its binary form without compiling again. Compiled languages and programs tend to be faster than interpreted or p-code languages, but require an extra step of compiling before running the application. Examples of compiled languages are C and C++, COBOL, and FORTRAN.
A program used to turn programming source code into an executable program.
A command line program that does not require (or perhaps even offer) a graphical user interface to run.
A Linux daemon that executes specified tasks at a designated time or interval.
A background process of the operating system that usually has root security level permission. A daemon usually lurks in the background until something triggers it into activity, such as a specific time or date, or time interval.
The operating system user interface, which is designed to represent an office desk with objects on it. Rather than physical telephones, lamps, and in/out baskets, the operating system desktop uses program and data icons, windows, taskbars, and the like. There are many different desktop environments available for Linux, including KDE and GNOME, that can be installed by a user. (Also see the definitions for GUI, Window Manager, and X Window System in this section.)
A program that serves as an intermediary between the operating system and a device (such as ports, drives, monitors, or printers) defining to the operating system what capabilities the device has and translating the operating system commands into instructions the device understands.
A packaging of the Linux kernel (core) with various user interfaces, utilities, drivers, and other software into a user deliverable. Often available as a free download or in a low-cost CD-ROM package. Popular distributions include Red Hat, SUSE, and Debian. Sometimes referred to as a “distro.”
Dpkg (Debian Package Manager)
A packaging and installation tool for Internet downloads, included with Debian Linux, but compatible with other distributions. It produces files with a .deb extension. Similar to RPM.
Emacs (Editing with MACroS)
A popular text editor, usually used as a console application. (Also, see Vi.)
One of several user interfaces (window managers). For more about Enlightenment, see:
(Also, see GNOME, KDE, and X Window System.)
A variable used in scripts or console commands that refers to various environment settings. A common environment variable is $HOME, which points to the current user’s home directory.
The part of a file which determines if a file can be executed directly. Files without the executable bit are considered data files. Note that it is usually possible to execute files without the executable bit set if a helper application is used. (For instance, perl ./noexec.pl will still run the application noexec.pl, even if the executable bit is not set.)
The trailing characters on a file name that are found after a period (.). The file extension usually describes what type of file it is. Unlike Windows, executables on Linux usually do not have a file extension.
A set of programs that tells an operating system how to access and interpret the contents of a disk or tape drive, or other storage medium. Common file systems include: FAT and NTFS on Windows and ext3 and ReiserFS on Linux.
A program that reads data (from a file, program output, or command line entry) as input, processes it according to a set of predefined conditions (for example, sorted alphabetically) and outputs the processed data. Some filters include Awk, Grep, Sed, and Sort.
A Linux command that provides information about users that are logged on.
In a multitasking operating system, such as Linux, the foreground process is the program that the user is interacting with at the present time (for example, data entry). Different programs can be in the foreground at different times, as the user jumps between them. In a tiered windowing environment, it is the topmost window.
FreeBSD (Free Berkeley Software Distribution)
Similar to Linux in that it includes many GNU programs and runs many of the same packages as Linux. However, some kernel functions are implemented differently. (Also, see BSD UNIX.)
Fsck (File System Check)
The command for scanning a disk for errors and fixing those errors if possible. Similar to the ScanDisk tool on Windows.
FTP (File Transfer Protocol)
A method of transferring files to and from other computers-often software repositories.
GCC (GNU C Compiler)
A high-quality C compiler governed by the GPL.
GIMP (GNU Image Manipulation Program)
A popular image editor for Linux.
GNOME (GNU Network Object Model Environment)
One of several user interfaces (window managers) for Linux, built with GTK+. For more about GNOME, see:
In verbal communication, the G is not silent, as in Guh-Nome. (Also, see Enlightenment, KDE, and X Window System.)
GNU (GNU is Not UNIX) Project
An effort of the Massachusetts Institute of Technology (MIT) Free Software Foundation (FSF http://www.fsf.org/ ) to develop and promote alternatives to proprietary UNIX implementations. GNU software is licensed under the GPL.
Same as Linux. So-called because many of the components included in a Linux distribution are GNU tools.
GPL (GNU General Public License)
A common usage and redistribution license. Any derivation of a work released under the GPL must also be released under the GPL or similar license. This includes application that interacts with a GPL library. For a copy of the GPL agreement, see:
Grep (Global Regular Expression® and Print)
A tool that searches files for a string of text and outputs any line that contains the pattern.
GRUB (GRand Unified Bootloader)
A partition boot manager utility, capable of booting operating systems. GRUB provides a graphical menu to select which operating system to boot. GRUB has replaced LILO on most distributions. (Also, see LILO.)
GTK+ (GIMP ToolKit)
A powerful, fast open source graphics library for the X Window System on Linux, used by programmers to create buttons, menus, and other graphical objects. In verbal communication, it is called GTK. (Also, see GNOME, Motif, and Qt.)
GUI (Graphical User Interface)
The collection of icons, windows, and other on-screen graphical images that provides the user’s interaction with the operating system. (Also, see Desktop and Window manager.)
Gzip (GNU zip)
The original file compression program for Linux. Recent versions produce files with a .gz extension. (A .z or .Z extension indicates an older version of Gzip.) Compression is used to compact files to save storage space and reduce transfer time. (When combined with Tar, the resulting file extensions might be .tgz, .tar.gz, or .tar.Z.)
Hard links are a cross between a shortcut to a file and a copy of a file. When hard linking, no data is copied, but a new entry to the original data is created. When the original file is deleted, the hard link pointing to the original data will remain. Hard links can only point to files on the same partition. (Also, see Symbolic Link.)
The directory the user is placed in after logging on, and where most (if not all) of a user’s files are stored. Usually found in as a subdirectory of /home. Sometimes referred to as $HOME, which is an environment variable that points to the current user’s home directory. Also referred to as ~, which is a shell shortcut that points to the current user’s home directory.
HTML (Hyper Text Markup Language)
The standard markup language for designing Web pages. Markup tags, or formatting commands, allow the Web page designer to specify highlighting, position graphics, create hyperlinks, and more.
HTTP (Hyper Text Transport Protocol)
The set of guidelines created for requesting and sending HTML-based Web pages.
The first process to run immediately after the operating system loads. It starts the system in single-user mode or spawns a shell to read the startup files, and opens ports designated as login ports.
Unlike a compiled program, which is converted from source code to an executable one time, by a compiler, and then run from its binary form, an interpreted program is converted to binary on the fly each time it is run, by an interpreter program. Interpreted languages (and thus their programs) tend to be slower than compiled and p-code languages, and generally have limited authorization to low-level operating system functions or direct hardware access. On the other hand, they are often included along with operating systems, and are usually easier to program than compiled languages. Examples of interpreted languages are BASIC, Perl, Python, and REXX/Object REXX.
An object-oriented programming language developed by Sun Microsystems™ to be operating system independent. Java is often used on Web servers. Java applications and applets are sometimes offered as downloads to run on users’ systems. Java programming can produce applications, or smaller Java applets. While Java can be compiled to native code, it is typically compiled to bytecode, which is then interpreted. (Also, see JIT Compiler.)
Small Java programs that are embedded in a Web page and run within a browser, not as a stand-alone application. Applets cannot access some resources on the local computer, such as files and printers, and generally cannot communicate with other computers across a network.
A cross-platform World Wide Web scripting language, vaguely related to Java. It can be used as a server-side scripting language, as an embedded language in server-parsed HTML, and as an embedded language for browsers.
JDK™ (Java Development Kit)
A Java programming toolkit from Sun, IBM, or others, available for Linux and other operating systems.
JFS (Journaled/Journaling File System)
A file system that includes built-in recovery capabilities. Changes to the index are written to a log file before the changes take effect so that if the index is corrupted (by a power failure during the index write, for example), the index can be rebuilt from the log, including the changes.
JIT (Just-In-Time) Compiler
A compiler for interpreted languages that allows programs to be automatically compiled into native machine language on the fly, for faster performance of the program.
Same as logging. Writing information to a journal (log) file as a method of tracking changes.
JVM™ (Java Virtual Machine)
Java run-time environment, required for the running of Java programs, which includes a Java interpreter. A different JVM is required for each unique operating system (such as Linux and Windows), but any JVM can run the same version of a Java program.
KDE (K Desktop Environment)
One of several user interfaces (window managers) for Linux, built with Qt. For more on KDE, see:
(Also, see Enlightenment, GNOME, and X Window System.)
The core of the operating system, upon which all other components rely. The kernel manages such tasks as low-level hardware interaction and the sharing of resources, including memory allocation, input/output, security, and user access.
An enhanced version of the Bourne Shell, including extensive scripting support and command line editing. It supports many scripts written for the Bourne Shell. (Also, see Bash.)
LGPL (Lesser GPL)
A variation of the GPL that usually covers program libraries. Any application can interact with an LGPL library or application, but any derived library must be licensed under the LGPL or similar license. For a copy of the GPL agreement, see:
LILO (LInux LOader)
A partition boot manager utility, capable of booting operating systems. LILO is not constrained to booting just Linux. Most distributions has replaced LILO with GRUB. (Also, see GRUB.)
An shortcut to a file or directory. (Also, see Symbolic link and Hard link.)
An open source UNIX-like operating system, originally begun by Linus Torvalds. The term “Linux” really refers to only the operating system kernel, or core. Several hundred people have contributed to the development of the Linux kernel. The rest of a Linux distribution consists of various utilities, device drivers, applications, a user interface, and other tools that generally can be compiled and run on other UNIX operating systems as well.
To store application or system messages or errors. Also, a file that holds this information.
A popular non-graphical (text-based) Web browser.
A set of instructions stored in an executable form. Macros can be application specific (such as a spreadsheet or word processing macro that performs specific steps within that program) or general-purpose (for example, a keyboard macro that types a user ID when Ctrl+U is pressed on the keyboard).
The Linux command for reading online manual pages.
MBR (Master Boot Record)
The first physical sector on a bootable disk drive. The place where the system BIOS looks when the computer is first booted, to determine which partition is currently active (bootable), before reading that partition’s first (boot) sector and booting from the partition.
An implementation of the OpenGL (Open Graphics Library) API (Application Programming Interface). It provides standard guidelines and a toolset for writing 2D and 3D hardware-assisted graphics software.
MIME (Multipurpose Internet Mail Exchange)
A communications protocol that allows text e-mail messages to include non-textual (graphics, video, or audio, for example) data.
A graphics library for Linux, developed by the Open Software Foundation (OSF now called The Open Group http://www.opengroup.org/ ) and used by programmers to create buttons, menus, and other graphical objects for the X Window System. (Also, see GTK+ and Qt.)
Identify a disk drive to the file system. Hard drives, CDs, and floppies all need to be mounted before use. Removable media usually needs to be unmounted before ejecting the disk. Most modern distributions automatically mount and unmount removable media. It is also possible to mount disk images (such as ISO files), network devices, and even links to other parts of the file system.
The location on a file system where a hard drive partition, removable media, or other resource is mounted.
The ability of an operating system to run more than one program, or task, at a time. A cooperative multitasking OS, such as Windows 98, requires one application to voluntarily free up resources upon request so another application can use it. A preemptive multitasking OS, such as Linux, Windows NT-based systems, or OS/2, frees up resources when ordered to by the operating system, on a time-slice basis, or a priority basis, so that one application is unable to hog resources when they are needed by another program. (Also, see Multithreading and Time-sharing.)
The ability of an operating system to concurrently run programs that have been divided into subcomponents, or threads. Multithreading, when done correctly, offers better utilization of processors and other system resources. A word processor can make good use of multithreading, because it can spell check in the foreground while saving to disk and sending output to the system print spooler in the background. (Also, see Thread.)
NFS (Network File System)
A file system that allows the sharing of files across a network or the Internet.
Someone new to the Internet, computers in general, or Linux specifically (for example, a “Linux newbie”).
A software development methodology that offers the programmer standard reusable software modules (components), rather than requiring the developer to write custom programming code each time. Using standard components reduces development time (because the writing and testing of those components have already been done by other programmers), and ensures a standard look and feel for programs using the same components.
OO See Object-Oriented.
A somewhat ambiguous term that refers to software that is released with its source code. The fact that the source code is provided does not necessarily mean that users can modify and redistribute the source code. The term is sometimes use interchangeably with “free software,” although they are not always the same. (Also, see Public Domain and Shareware.)
OSS (Open Sound System)
A device driver for accessing sound cards and other audio devices under Linux. It evolved from the Linux Sound Driver, and supports most popular audio chips and adapters. OSS has been replaced by ALSA on most distributions. (Also, see ALSA.)
OSS (Open Source Software)
See Open Source.
The user who has privileged access to a file; typically, the user who created the file.
P-code (Pseudo-code) Language
A type of Interpreted language. P-code languages are something of a hybrid, falling between compiled languages and interpreted languages in the way they execute. Like an interpreted language, P-code programming is converted to a binary form automatically when it is run, rather than having to be compiled. However, unlike a compiled language, the executable binary file is stored in pseudo-code, not machine language. In addition, unlike an Interpreted language, the program does not have to be converted to binary each time it is run. After it is converted to P-code the first time, the pseudo-code version is used for each additional execution. P-code languages (and thus their programs) tend to be slower than compiled languages and programs but faster than interpreted languages, and they generally have authorization to some low-level operating system functions but not direct hardware access. They are often included along with operating systems, and some p-code languages are easier to program than compiled languages. Examples of P-code languages are Java, Python, and REXX/Object REXX.
PAM (Pluggable Authentication Modules)
A replaceable user authentication module for system security, which allows programs to be written without knowing which authentication scheme will be used. This allows a module to be replaced later with a different module without requiring rewriting the software.
The name for the Linux equivalent of the Windows Taskbar.
A contiguous section of a disk drive that is treated by the operating system as a physical drive. Thus, one disk drive can have several mount points assigned to it.
A variety of bitmapped fonts to be used with the X Window System.
PDF (Portable Document Format)
Binary files created with Adobe Acrobat or other programs capable of producing output in this format. Used for producing operating system-independent documents, which can be viewed using Acrobat Reader or other programs, including Web browsers equipped with an Acrobat Reader plug-in.
Perl (Practical Extraction and Report Language)
A common programming language. It is often used on Linux Web servers for generating CGI scripts.
The authority to read and write files and directories, and execute programs. Varying permission levels can be assigned by the Superuser, or root operator, on a file-by- file, directory-by-directory basis or by account name (User ID). Permissions are often referred to in two forms of shorthand. When using shorthand, the first set regards the file owner, the second a file group, and the third is in reference to everyone. The first form of permission is to abbreviate the permission, with rwx meaning read, write, and execute respectively. The more common form uses a numerical value for permissions, where the number is the sum of permissions, with read equal to four, write equal to two, and execute equal to one. For instance, a file where the owner can read and write, the group can read, and everyone else who has no access would be abbreviated as 640.
PGP (Pretty Good Privacy)
A high-security, public-key data encryption program for Linux and other operating systems.
The process of taking a program written for one operating system platform and modifying it to run on another OS with similar functionality. There is generally little or no attempt to customize the program to take advantage of the unique capabilities of the new operating system, as opposed to optimizing an application for a specific operating system.
A term referring to software that is designed to be used on more than one operating system with only minor modifications and recompilation.
POSIX (Portable Operating System Interface for uniX)
A set of programming interface standards governing how to write application source code so that the applications are portable between operating systems. POSIX is based on UNIX and is the basis for the X/Open specification of The Open Group.
A page description language developed by Adobe Systems that tells a printer how to display text or graphics on a printed page.
A wide variety of fonts that can be used with OS/2, Microsoft Windows, and the X Window System. Font files include those with .afm, .pfa, and .pfb extensions. Sometimes called Adobe Type 1 fonts, or ATM (Adobe Type Manager) fonts. PostScript fonts typically require a PostScript-compatible printer. (Also, see BDF Fonts and TrueType Fonts.)
An executing program. (Also, see Multitasking and Multithreading.)
Software that is available to be used and modified by anyone, for any purpose, and might even be incorporated for distribution in commercial software. Public domain software is not copyrighted, and no rights are retained by the author. (Also, see Open Source and Shareware.)
Public Key Encryption
A method of data encryption that involves two separate keys: a public key and a private key. Data encrypted with the public key can be decrypted only with the private key and vice versa. Typically, the public key is published and can be used to encrypt data sent to the holder of the private key, and the private key is used to sign data.
An object-oriented p-code programming language.
A powerful, fast open source graphics library for the X Window System on Linux, which is used by programmers to create buttons, menus, and other graphical objects. In verbal communication, Qt is pronounced the same as the word “cute.” (Also, see GTK+ and KDE.)
A list of tasks awaiting execution, as in “the print queue.”
RAID (Redundant Array of Independent/Inexpensive Disks/Devices)
A method of providing data redundancy, improved performance, and quick data recoverability from disk crashes, by spreading or duplicating data across multiple disk drives. Commonly used RAID types include RAID 0 (Data Striping), RAID 1 (Disk Mirroring), and RAID 5 (Striping with Distributed Parity). RAID configurations typically require identical drives (same capacity and even brand and model). RAID arrays appear to the operating system as a single device.
A script file containing the startup instructions for a program (an application or even the operating system). The file, to be executed automatically when the operating system is started, contains a list of instructions (commands or other scripts) to run.
RCS (Revision Control System)
A suite of programs that controls shared access to files in a group environment and tracks text file changes. Generally used for maintaining programming source code modules.
A utility for obtaining information about a Linux system. It is used to query and set the image root device, the video mode, the swap device, and a RAM disk.
The user ID with authority to perform all system-level tasks. (Also called Superuser.)
The underlying session in which the Linux desktop runs.
RPM (Red Hat Package Manager)
A packaging and installation tool for Internet downloads, included with some Linux distributions. It produces files with a .rpm extension. Similar to Dpkg.
A set of commands stored in a file. Used for automated, repetitive execution. (Also, see RC File.)
SCP (Secure Copy)
A method for securely copying files between local and remote hosts. SCP uses SSH as a back-end. (Also, see SSH.)
A complete interaction period between the user and the operating system, from login to logoff.
A form of commercial software, where it is offered as “try before you buy.” If the customer continues to use the product after a short trial period, they are required to pay a specified, usually nominal, fee. (Also, see Open Source and Public Domain.)
A text-mode window containing a command line interface to the operating system.
The user input area of a shell. Whereas in a DOS shell the command prompt is designated by a Greater Than (>) symbol, in Linux it is usually a Percent (%) symbol, Dollar sign ($) or other special character, depending on the shell used. (Also, see Command Prompt.)
A script designed to be run automatically when a shell is started.
The / symbol. Slash is used in file path names, instead of the backslash, \, used in the DOS, Windows, and OS/2 operating systems.
Programming commands in their raw state as input by a programmer. Some programming languages allow the commands to be executed on the fly by a program interpreter. Other languages require the commands to be compiled into executable programs (binaries) before they can be used. In the Linux world, some software is distributed as source code only; other packages include both source and binaries; still others are distributed in binary format only.
Spool (Simultaneous Peripheral Operation On-Line)
To send data to a program that queues up the information for later use (for example, the print spooler).
SQL (Structured Query Language)
The language used for manipulating records and fields (rows and columns) in a relational database. Sometimes pronounced “sequel.”
SSH (Secure Shell)
A secure protocol for logging in to a remote machine. Many protocols can be “tunneled” through SSH, such that connections travel through a SSH connection between two machines instead of traveling unencrypted across the network.
A sequence of characters, as in a “search string.”
Usually synonymous with root user.
To temporarily move data (programs or data files) from random access memory to disk storage (swap out), or back (swap in), to allow more programs and data to be processed than there is physical memory to hold it. Also called Virtual Memory.
Where swapped data is temporarily stored on disk. Linux uses a dedicated disk partition for swap space, rather than a specific swap file.
An shortcut to a file or directory. Sometimes called a symlink. If the original file is deleted, the symbolic link will no longer work. (Also, see Hard link.)
To force all pending input/output to the disk drive.
The Linux System Logger, where all system messages or errors are stored.
A command in a markup language, such as HTML, to display information in a certain way, such as bold, centered, or using a certain font.
Tar (Tape ARchive)
A file packaging tool included with Linux for the purpose of assembling a collection of files into one combined file for easier archiving. It was originally designed for tape backup, but today can be used with other storage media. When run by itself, it produces files with a .tar extension. When combined with Gzip, for data compression, the resulting file extensions can be .tgz, .tar.gz, or .tar.Z.
A file created by the Tar utility, containing one or more other archived and, optionally, compressed files.
A popular macro-based text formatter. The basis for other such formatters, including LaTeX and teTeX.
A program for editing text files. Similar to a word processor, but without most of the formatting functions (such as margins, italics, and fonts). Often used for writing or editing scripts, programs, and plain text files.
A program that prepares a text document for printing, allowing the user to perform many layout functions, such as margins, headers, footers, indentation, pagination, and justification.
TFTP (Trivial File Transfer Protocol)
A simplified version of FTP without authentication or many other basic features of FTP.
A small piece of programming that acts as an independent subset of a larger program. A multithreaded program can run much faster than a monolithic, or single-threaded, program because several different tasks can be performed concurrently, rather than serially (sequentially). Also, threads within a single application can share resources and pass data back and forth between themselves.
A method of allowing multiple users to share a processor by allocating each user a portion of the processor resources on a timed basis and rotating each user’s processes within those time segments. (Also, see Multitasking.)
A command that changes the date and time stamp of a file without affecting the contents. If passed a file name that does not exist, touch will create an empty file.
A wide variety of fonts designed to be printer-independent, unlike PostScript fonts. (Also, see BDF Fonts and PostScript Fonts.)
The name of the fictional Linux penguin mascot.
The command for unmounting a hard drive partition, removable media, or other resource. (Also, see Mount.)
UNIX began as a proprietary operating system developed by Bell Laboratories in the 1960s. It eventually spawned a number of mutually incompatible commercial versions from such companies as Apple (Mac OS X), Digital (Digital UNIX), Hewlett-Packard (HPUX), IBM (AIX®), NeXT (NeXTSTEP), and others.
A set of programs and protocols that have become the basis for a worldwide network of UNIX computers. Named after the UNIX to UNIX Copy Program.
A popular text editor, usually used as a console application. Also used when discussing newer version, Vim. (Also, see Emacs.)
A method for expanding the user’s workspace beyond the boundaries of the computer screen. The desktop can be scrollable left and right, up and down, as though a larger desktop were positioned behind the glass screen and moved around to reveal icons, windows, and other objects that were “off-stage,” or out of view. Alternatively, as with the KDE desktop, multiple buttons can be available, each of which displays an area of desktop equal to the size of the glass screen and which can each contain different objects.
Virtual Machines (VMs) are features of central processor chips that isolate an area of memory from the rest of the system. Because operating systems and applications run in a “protected mode” environment, if a program freezes in one Virtual Machine, it will not affect the operation of the programs and operating systems running outside of that Virtual Machine.
The process of using a portion of disk space as a temporary storage area for memory. Synonymous with Swap.
A graphical user interface programming object (such as a button, scroll bar, or check box) for the X Window System. (Also, see X Window System.)
The graphical user interface (GUI) that runs on top of the X Window System to provide the user with windows, icons, taskbars, and other desktop objects. (Also, see Desktop.)
Another name for the current directory, or the directory in which the user is currently working.
Another name for the Root Window, or Desktop.
A program used to start another program.
X Window System
A graphical windowing environment for UNIX. The underlying program required by many user interfaces. (Also, see Desktop and Window Manager.)
Version 11 of the X Window System.
XDM (X Display Manager)
User-friendly login front end for the X Window System.
XML (eXtensible Markup Language)
A powerful new markup language for designing data; similar to HTML, but allows programmers to define their own markup tags, or formatting commands.
A popular form of file compression and archiving available on many operating system platforms, including Windows and Linux. Popular tools include PKZip/PKUnzip and Zip/Unzip. Zipped files will have a .zip extension.
The redirection symbol; it is often used to send the output from a command to a text file. For example, the following command sends the current directory list to a file called output.txt, overwriting what had previously been in that file:
ls -a > output.txt
(Also, see Append Symbol and Piping Symbol.)
The append symbol; it is often used to send the output from a command to a text file, appending the data to the end of the file, rather than replacing the existing content. For example, the following command sends the current directory list to a file called output.txt, and adds it to the end of the file.
ls -a >> output.txt
Repeating the command will continue to add new data to the end of the file. (Also, see > and |.)
The piping symbol (the Shift+Backslash character, above the Enter key on a typical 101-key keyboard); it is often used to feed the output from one command or program to another. For example, to search for a previously entered command with the word “mcopy” in it, use the following command:
history | grep mcopy
(Also, see Append Symbol and Redirection Symbol.)
/ See Slash.
~ See Home Directory.
If you cannot find a word you are looking for here, there are many other sources of acronyms, abbreviations, and general computing terms (not all of them specific to Linux) from which to choose. Because some terms are likely to appear in one dictionary, but not another, and because some definitions can be clearer or more comprehensive in one source than in another, here is a selection to choose from, in alphabetical order:
Free Online Dictionary of Computing
IBM Terminology Web site
Ugeek Technical Glossary