MD5 is an algorithm to calculate a checksum which can be used e.g. to check
if a file has been changed.
What  does that  mean  for you?  You could  calculate  a checksum  (perhaps
through using the tool included in 'md5-0.0.2-setup.zip' in this directory)
of the downloaded file  and compare it with the corresponding MD5  checksum
to make sure that the file has been downloaded correctly.