File search
find / -name file1	search file and directory into root filesystem from '/'
find / -user user1	search files and directories belonging to 'user1'
find /home/user1 -name \*.bin	search files with '. bin' extension within directory '/ home/user1'
find /usr/bin -type f -atime +100	search binary files are not used in the last 100 days
find /usr/bin -type f -mtime -10	search files created or changed within 10 days
find / -name \*.rpm -exec chmod 755 '{}' \;	search files with '.rpm' extension and modify permits
find / -xdev -name \*.rpm	search files with '.rpm' extension ignoring removable partitions as cdrom, pen-drive, etc.…
locate \*.ps	find files with the '.ps' extension - first run 'updatedb' command
whereis halt	show location of a binary file, source or man
which halt	show full path to a binary / executable