Still not sure what the heck Twitter is or why you'd want to use it? I understand completely: Friends and family members are constantly asking me, "What the heck is Twitter, and why would I want to use it?"
I have to admit, I'm not very good at explaining it. But no matter, because now I can refer everyone to "The Complete Guide to Twitter," a free 40-page guide from MakeUseOf.
Author Mark O'Neill explains what the service does, why it's actually worth using, and how to sign up for an account.
You'll also get hands-on training on subjects like using the interface, sending Tweets from your desktop, signing up for automated Twitter "bots," and so on.
The guide is available for download in PDF format, though you can also read it online at Scribd.com. It's definitely worth a look if you're confused by Twitter or just need help making the most of the service.