Welcome to Wikipedia! This page will teach you how to easily fix vandalism that you may come across while browsing the site.
What is vandalism?
Vandalism is editing deliberately intended to obstruct the project's purpose of building a free encyclopedia. Examples include adding irrelevant obscenities or jokes, illegitimately blanking pages, and inserting obvious nonsense. Not all bad edits are vandalism. If an edit is misguided but plausibly made in good faith, you can try undoing it once, but you should use the dispute resolution process if it is restored. Most vandalism is obvious, so don't be afraid to fix it.
Replace PAGENAME with the page where you noticed the vandalism, keeping the double brackets ([[ ]]).
Replace BRIEFLY DESCRIBE THE VANDALISM HERE with a concise description of the vandalism.
Click Publish changes.
Warn the vandal: It is good practice (although not strictly necessary) to give the vandal a warning on their personal talk page after you revert them.
Report chronic vandalism to administrators: If the vandal persists after receiving a level-4 warning on their talk page (which tells them that they may be blocked the next time they vandalize), you should report them to the administrator intervention against vandalism noticeboard.
Find more vandalism to fix: If this was satisfying, you can help identify and revert vandalism with the WikiLoop DoubleCheck tool, which presents a feed of edits flagged by an algorithm.