[]

This wildcard is like a ?, but allows more specificity. To use this wildcard, place any characters you'd like to match inside the []. The resultant expression will match a single occurrence of any of these characters. You can also use - to specify a range, and even combine ranges. Examples:

• myfile[12] will match myfile1 and myfile2. The wildcard will be expanded as long as at least one of these files exists in the current directory.
• [Cc]hange[Ll]og will match Changelog, ChangeLog, changeLog, and changelog. As you can see, using bracket wildcards can be useful for matching variations in capitalization.
• ls /etc/[0-9]* will list all files in /etc that begin with a number.
• ls /tmp/[A-Za-z]* will list all files in /tmp that begin with an upper or lower-case letter.