Wikis allow you to see exactly what has changed between different revisions of a page. There are a number of ways to access this difference:
- When viewing the page history through the "history" tab, clicking the (cur), (last), or Compare selected versions options will display the differences;
- Similarly, opening Special:Recentchanges or Special:Watchlist will display a (diff) link with each entry;
- Finally, one can step forward or backward in time from a diff that you are already looking at.
How to read a diff
Diffs can be difficult to decipher at first; changes are generally highlighted with a yellow background on the left side's older version and a green background on the right side's new version. Changed text will show in a bold red font; added/removed text generally remains black. Sometimes green/yellow lines will appear blank with no text at all; this usually means a blank line or space was added, removed, or changed.