Debian installation question

[propaine]

I'm thinking about replacing my FC2 with Debian, so I went to

http://people.debian.org/~shane/netinst-speakup/

After looking at the very short read-me file, I tried to figure out what I'd need to download for the installation.  What are the differences between

speakup_netinst-3.1r0a-1.iso

speakup_netinst-3.1r0a-1.iso.md5

and
speakup_netinst-3.1r0a-1.iso.sign

Would I need to use more than one of these for the installation?

Thanks!

Propaine