find [path...] [expression]
Search criteria:
-name pattern : Base of file name
-iname pattern : Base of file name but ignore case.
-atime n : File was last accessed n*24 hours ago
-type c : File is of type c:
d=directory, f=regular file, l=symbolic link, ...
Examples:
find . -iname "*.gif"
locate: List files in databases that match a pattern.
Options:
-i, --ignore-case : Ignore case in both the pattern and the file names
Examples:
locate .emacs