What does beta update versions mean?

I found a file hippo update checker that scans computer for updates.My computer is xp pro windows and two questions I have is has anyone heard of hippo update checker is it good? Also there is options to show updates only and show beta versions updates I'm new to computers what is beta versions and do I want do updates on my xp windows for beta versions? because the scan said on beta version I need three updates on spybot and limewire and something else not yahoo.