Wikipedia:ROLLBACK

An editor with rollback rights sees a rollback button next to relevant revisions on their watchlist, in page histories, and in certain other places. A single click on this button reverts the edit in question, as well as any other consecutive preceding edits made by the same user.

Rollback is available to all administrators and can be given to other users upon request, subject to the approval of an administrator. A user who has been assigned this right explicitly is called a rollbacker. There are currently administrators and rollbackers (6,996 total), not including global rollbackers and who have been assigned the right across all projects.

Standard rollback may only be used in certain situations – editors who misuse standard rollback (for example, by using it to reverse good-faith edits in situations where an explanatory edit summary would normally be expected) may have their rollback rights removed. Since rollback is part of the core administrator tools, an admin could be stripped of their administrative privileges entirely to remove those tools.

Users with rollback permission have extra "rollback" links next to revisions on the recent changes page, page histories, diffs, user contribution pages, and their watchlist:

Clicking one of these links restores the page to the most recent revision that is not made by the revision's author. This appears in the page history with a generic summary that looks like this:

A link to the reverted user's contribution history is provided, so that it may be easily checked for further problematic edits. It does not appear if you are reverting contributions done by a user whose username has been removed, the result being:

Rules and limitations:

...
Wikipedia