The Internet Archive Way Back Machine ist a big archive which stores webpages since 1996. If you want to see for example, how your webpage looked in 2005, just go to archive.org and type in your websites URL.
If your webpage was found, you will see a list of dates, when your webpage was archived by the Way Back Machine. Click the date you want to see and you will see the website how it was archived at the selected date.
So, although not every snapshot works, I think it’s a great tool. Go and test it yourself.