Checking an item's historyEdit
Wikidata maintains a record of every edit that was ever made to an item. Wikidata's edit history is a very useful tool for tracing the way that information about an item has been changed over time.
Clicking on the "View history" link at the top of any page will show you a list of changes to the item.
You can see the date the edit was made, the editor who made the edit, the current size of the page (in bytes), the size of the change made, and an edit summary that briefly describes what was done. If you're familiar with edit summaries in Wikipedia, you'll notice that these are a little different in that the edit summaries on items are automated.