This is how Google gets webpages for people to search. Mike could describe this better than me, but I'll take a shot.
Google sends out their "spiders" looking for new and updated material. When they find some, they store it for searchable material in their search engine.
Because our material is frequently changing or being updated, Google likes to hang around A LOT. In fact, since August 7th of this year, Google has hit us 26065 times (and counting!). That "Google [spider]" that you see is them storing our material for searchable use.
I know I've said this before, but it can never hurt to stress too much - we often rank near the top for certain issues and debates at Google. Because of this,
thousands of people have the potential to see your posts. The first impression you make on a stranger can stand for a lifetime. Proper spelling, grammar and punctuation will take you a long way as far as credibility goes. Also, if you are starting a new thread, it helps to make the title of it something like what people may search on in Google (assuming you want more than just our members to find it).
I hope that helps. If not, I'll let Mike know he should drop by this thread and elaborate.