And just in case people are unsure what a wiki is, or how to edit one, it’s a post that’s been opened up so it’s editable by anyone Trust Level 1 or higher. You can pull up the wiki editor by clicking on the ‘pencil in a square’ icon in the lower right corner of a wiki post:
And you can make any amendments you fancy, just like editing one of your own posts. 
There’s also a visible edit history in the top right, so you can flick back through and see all the changes, and who made them. 
If you want to practice with one before getting stuck in properly with these then you can have a play with the dummy one @Green_Eyed_Girl set up in the Sandbox.