What did Steam look like when I joined?
Drag the dial to the month, or paste your Steam profile and the time machine starts at the month your account was made, read from Steam's public profile data. The window shows Steam's front page as the Internet Archive's Wayback Machine captured it that month.
Where do the pages come from?
Each month is the Wayback Machine's own capture of Steam's front page (steampowered.com until autumn 2008, then store.steampowered.com), picked near the middle of the month, in English and priced in US dollars. While the months play, the window shows a still of each capture; when it stops, the archived page itself opens, links and all.
Are those the prices games cost then?
Yes. The top sellers under the window, their prices and their sale prices are read off that month's page. Today's price is Steam's US list price now for the same game or package.
Why is a month missing?
The archive kept no usable capture of the front page that month, which is most of 2006. The window shows the month before it instead.