7 Glossary

Active window
At any one time, there is only one window on an X Windows screen which accepts typed input. This window is said to be active, or to have the input focus.

Further details...

Arguments
A command may modify its behaviour according to certain extra words typed after its name on the command line. These extra words are command line arguments, and must be separated by spaces and/or tabs. The effect of command line arguments depends on the command.

Further details...

Browser
A program that assists you in reading World Wide Web documents.

Further details...

Command Line Interface
A user interface which executes commands typed in by the user, as opposed to a graphical user interface.

Further details...

Current directory
See Working directory.
Directory
A special kind of file which can "contain" other files in a list. Use the ls command to view a directory listing.

Further details...

File
A file is a named region of storage on a storage device, most commonly a hard disk. A file has a name, and contains an arbitrarily long sequence of bytes.
Filename
A string of characters used to identify a file. Usually filenames are familiar words, and should not contain any spaces or punctuation (although underscores, hyphens, periods and colons are fine in Unix).
Frames
Netscape has the capability of splitting a browser window into separate viewing areas called frames, which can display different documents independently. This document is designed to be viewed using a browser which is aware of the frame syntax. There are further details on how to use frames at the Netscape web site, which you can best visit by clicking the animated "N" at the top right of the Netscape window.
Graphical User Interface (GUI)
A user interface which represents programs and files by icons and executes commands at the click of a mouse.
HTML
The abbrevation HTML stands for Hypertext Markup Language, the language in which hypertext documents are represented to the browser on the World Wide Web. You don't have to know how HTML works unless you are interested in creating your own WWW pages. For more, see On HTML... on the Mosaic Help menu.
Hypertext
A hypertext document is a document which contains embedded links which can be used to navigate the document interactively.

Further details...

Icon
A small image which represents a program or file in a graphical user interface.
Link
A highlighted item in a hypertext document, which refers to another part of the document, or to another document altogether. To follow, or activate a link, click the mouse pointer on it. The new document should appear, possibly after a few seconds' wait.

Further details...

Manual page
Unix systems come with an online user's manual, which is sectioned into 'pages' (or 'man pages' for short), one for each command or topic. These pages can be accessed by using the man or xman commands.

Pathname
A pathname is a filename, but the term pathname is used to emphasize that the file could be either a directory or a plain file.
Permissions
Each file in Unix has certain permission attributes, which determine who is allowed to read, write or execute the file. If you attempt to remove a file from a directory for which you have no write permission, Unix will refuse, with the error Permission denied.
Plain File
A file which holds data to be read by a program or by the user, as opposed to a directory.
Prompt
A prompt is a short string of characters which a shell produces to let you know it's okay to type a command now. A typical prompt might look like: 
(myname@gamba)
Relative pathname
A pathname beginning with anything other than ~ (tilde) or / (slash). It is interpreted by Unix as the location of a file relative to the current working directory of either the shell (see pwd), or any other application.
Root directory
The top directory in a unix filesystem. It is always named '/', and contains every file and directory on the computer. It can be defined as the unique directory which is its own parent directory.

Further details...

Root menu
A menu that pops up on your root window, with several handy programs on it.

Further details...

Root window
The background of your X Windows screen. If you're not tidy with your windows, you soon won't be able to see the root window anymore!
Shell
A shell is a program which interprets your typed commands via a command line interface.
Text Editor
A text editor is a program which allows you to view and edit the contents of a file in raw text form. A text editor does not interpret the contents of the file to mean anything.

Further details...

Text insertion point
In a text window, the text insertion point is a vertical bar which shows you where the text you type will next appear. Generally, it can be placed anywhere by clicking the mouse where you want to type. Text will not appear in a window at all unless it is an active window.
URL
The abbrevation URL stands for Uniform Resource Locator, which is fancy talk for "most general address format on the World Wide Web". To read more on URLs, choose "On URLs" from the Mosaic Help menu.
Window manager
A window manager is a program which places a frame around all the windows on your X windows screen, allowing you to control the position and size of each window interactively using the various elements of the window frame.

Further details...

Working directory
Every program has a working, or current directory, which is the base for relative pathnames accessed from that program. For example, if the working directory of a text editor program is /home/ugrad/myname/docs, then a relative pathname mydoc.txt is interpreted as: /home/ugrad/myname/docs/mydoc.txt

Don't forget about the .. shorthand; it always stands for the parent directory of the current (or last-named, if it occurs in a long pathname) directory. In the previous example, a file /home/ugrad/myname/hello.m can be referenced as ../hello.m

The working directory of a program is usually assigned to be the current working directory of the shell from which the program was started.

Further details...

World Wide Web
The World Wide Web, or WWW for short, is a massive collection of hypertext documents, linked together over the Internet.

Further details...

Keith Orpen, who is still writing this, would like to hear your comments and suggestions.