grep pattern file
Search for pattern in file
grep -r pattern directory
Search recursively for pattern in directory
locate name
Find files and directories by name
find /home/john -name ‘prefix*’
Find files in /home/john that start with “prefix”
fine /home -size +100m
Find files larger than 100MB in /home
whereis program
Display the location of the binary, source and
manual page files of program
which program
Display the path of executable that would run if
program is executed.