The place to experiment with editing Wikipedia is called the sandbox. It’s aptly named, because the letters you write in this sand will get written over by other users; periodically, like a big wave, a program script comes along and wipes the whole thing clean. It’s also a good place to start because it’s a reminder that change is a constant in Wikipedia; both the software and the rules create by the human editors are always evolving, and if you don’t visit the site very often, both can seem alien in short order.
Visit the Wikipedia sandbox, and click on the blue link that says “edit” to begin. When you’re done, click the “save page” button down at the bottom, and whatever you’ve typed will forever become a part of Wikipedia.
Well . . . yes and no. As noted above, other users may come along and remove/change/append to your work, and on this page in particular, all the text gets removed automatically from time to time. However, nothing is ever really lost on the internet, and on Wikipedia, this is particularly easy to see: just click on the link marked view history to see just about everything ever done to this page since it was created in December, 2002.
The sandbox may become one of your most familiar haunts as you learn about editing Wikipedia, because it’s a safe way to experiment with using the ever-changing MediaWiki software that powers the site. The lesson of the sandbox is that no edit cannot be undone, but a history of all of those edits is kept forever like a Domesday Book.