GNU/Linux Commands for Beginners: which and whatis

commandline session

$which ls
/bin/ls
$which firefox
/usr/bin/firefox
$which grep
/bin/grep
$which whatis
/usr/bin/whatis
$whatis which
which (1)            - locate a command
$whatis whatis
whatis (1)           - display manual page descriptions
$whatis linux
linux: nothing appropriate.
$whatis kcore
kcore: nothing appropriate.
$whatis mysql
mysql: nothing appropriate.
$whatis locate
locate (1)           - find files by name

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