Installing md5 package into ubuntu

Hi i want to install md5 package into ubuntu. any idea how?

Apparently applying md5sum and md5 on a string (not a file) gives a different value! The one that I need to use is the md5 command, but it says command not found when i type md5 in bash.

AFAIK, md5sum is the command which calculates the md5 !

May be i'm wrong...
But can you explain If that command is not available how are you telling that both differs ?!!

thegeek is right. The command you want is md5sum.

which md5sum
/usr/bin/md5sum

To check a md5 crc stored in a file use -c.

example.

md5sum -c md5sums.txt