From LQWiki

A dot file is a file that is not visible by default to normal directory-browsing tools (on Unix, files named with a leading dot are, by convention, not normally presented in directory listings). They are, in a sense, "hidden", to use the terminology of Windows.

For this reason, many programs define one or more dot files in which startup or configuration information may be optionally recorded; either a program can create a dotfile with configuration, or a user can customize the program's behavior by creating the appropriate file in the current or home directory. Therefore, dot files tend to creep with every nontrivial application program defining at least one, a user's home directory can be filled with scores of dot files, of course without the user's really being aware of it.

In the shell, a * is not meant the same as in a regular expression, for one, because it would include the current directory, "." and parent directory "files" (See glob). As such, never use .* to affect all dot files for this reason! Instead, use .[A-Za-z0-9]* In bash, you can also change the dotglob variable to let * affect dot files. This will not affect "." and "..".

See also

• profile
• rc file

This article is based, in whole or in part, on entry or entries in the Jargon File.