whatis - display one-line manual page descriptions

syntax
$ Whatis [ command ]

$ whatis cp
$ whatis ls
$ whatis df
$ whatis du
$ whatis free
$ whatis cp ls df du free

To get help options
$ whatis --help

To get debugging information
$ whatis -d cp
$ whatis -d pwd

To get verbose details
$ whatis -v pwd
$ whatis -v free

To use regular expressions with this 
$ whatis -r free
$ whatis -r ls
$ whatis -r pwd

To use wildcard with this
$ whatis -w free



regards,
T.Dhanasekar