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 | This page in a nutshell: If you need to prove who did what where and when, it's essential to provide diffs as evidence. |
"So the next time an editor, or anybody else, urges you to "talk about indeffing", I urge you to reply "Shut up and show them the diff."
"I'm from Missouri. You have got to show me."
Wikipedia keeps a record of everything (more or less), and it can all be accessed by judicious use of diffs, which provide a link to a specific change at a specific point in time. The reason a diff is so important is it provides a comprehensive set of changes to an article by a specific user, at a specific time, with the edit summary they used. In other words, it shows exactly who changed what in an article, and is a smoking gun that easily clarifies things.
Did I do that?
editSometimes, I (and, probably, you) get a message from a bot, saying there was a problem with an edit. For instance, DPL bot occasionally turns up to tell you that you've added a link to a disambiguation page, which you should fix. Unfortunately, if you've made large amounts of edits in a small amount of time (perhaps you're busy copyediting your favourite article into shape for a featured article candidate), it can be difficult to identify which edit the bot's complaining about, and what the relevant context is. In this case, delivering a specific diff can help locate problems more quickly.
Heated arguments
editWhen you get involved in a dispute, particularly if it gets as far as ANI, emotions are already running high and tempers are frayed, and there's a great temptation to cry out about how awful the other editor is and how much of a misery they are making your life. Resist the urge to "get personal" at all costs, as it can come back to haunt you. As well as providing a clear and unambiguous record of changes, diffs allow any administrator or anyone else investigating to get to the heart of the evidence with one click. Because administrators baulk at wading through a large complaint to identify what the problem actually is, and prefer to get to the facts quickly, presenting diffs as a link means it's much more effective for action to be taken. Furthermore, supplying diffs also gives the impression to administrators that you understand the relevant procedures and have done your homework first, which allows you to be taken more seriously.
Unblock requests
editIf you somehow get blocked, understanding how to use diffs are your essential defence council. While diffs get a result in a similar manner as the noticeboards, obviously the importance is increased here, as your ability to edit Wikipedia is at stake, not just a complaint being ignored. Saying "I understand this ([1]) was wrong, and won't do it again" with a well-placed diff gives you the best opportunity to make amends and make a productive return to editing.
So next time you rush at full pelt to create that ANI thread without lining your ducks up in a row first, don't be surprised if you get greeted with the retort of "Shut up and show them the diff".