Wildcards

Using wildcards (which is also known as globbing) allow you to select filenames based on patterns of characters.

Wildcard	Meaning
*	Matches any characters
?	Matches a single character
[characters]	Matches any character that is a member of the set.
[!characters]	Matches any character that is not a member of the set.
[[:class:]]	Matches any character that is a member of the specified class.
^	Match expression at the start of a line, as in ^A.
$	Match expression at the end of a line, as in A$.
\	Turn off the special meaning of the next character, as in \^.
.	Match a single character of any value, except end of line.
\{x,y\}	Match x to y occurrences of the preceding.
\{x\}	Match exactly x occurrences of the preceding.
\{x,\}	Match x or more occurrences of the preceding.

Character classes:

[:alnum:]	Matches any alphanumeric character
[:alpha:]	Matches any alphabetic character
[:digit:]	Matches any numeral
[:lower:]	Matches any lowercase letter
:upper:]	Matches any uppercase letter

Character ranges:
Using character ranges like [A-N] may or may not work.
eg:

[![:digit:]]*

Any file not beginning with a numeral

Wildcards support in GUI

In Nautilus (the file manager for GNOME), you can select files using the Edit/Select Pattern menu item. Just enter a file selection pattern with wildcards and the files in the currently viewed directory will be highlighted for selection.
In Dolphin and Konqueror (the file managers for KDE), you can enter wildcards directly on the location bar. For example, if you want to see all the files starting with a lowercase “u” in the /usr/bin directory, type “/usr/bin/u*” into the location bar and it will display the result.