Whether you realize it or not, every change made to every page on Wikipedia is saved forever, and the page history is where you'll find it. This is another link in the top tabs, and usually appears as "View history".
Click that link, and you'll see a reverse-chronological listing of the last 50 edits, about one per line. There's a lot to take in! Left to right, each line contains:
- Links to show how one version compares with other versions
- The date a change occurred
- Who was the editor responsible
- How big the page was at the time, and how much it changed
- The reason for the change
Additional links on the page let you jump further back in time, isolate certain date ranges, or find other sorting tools. But for most purposes, history pages are an access point for something even more important: diffs. We'll cover those next week.