If you want to get to Facebook on a computer, it's easy. Just go to facebook.com. If you want to find Facebook on any mobile device, use the dedicated mobile site, m.facebook.com. But the easiest way to navigate Facebook on your smartphone is to use the Facebook app.
First, you'll need to download the app. Visit your app market, which is usually accessible on your smartphone, and install the Facebook app with just a few taps of your finger. It's really that easy. Some phones make it even easier by having the Facebook app already installed on your phone. Two hundred and fifty million mobile users can't be ignored, after all.
Once you've got the app, you need a Facebook account. You can do this through the app when you first set it up, or you can use your computer. In either case you'll choose a user name and password, and give Facebook an email for sending notifications and account information. Then you can set up a profile with your hobbies, hometown, relationships, a picture of you and your cat -- whatever you like. If you've already got a user name and password, the Facebook app will prompt you to enter the first time you tap that blue-and-white "F" in your phone's app directory.
There are apps for just about every smartphone out there, including iPhone, Android, Palm, Blackberry and Windows phones. You can also find Facebook apps for tablet computers, which run on similar systems. As of July 2011, you can also get an app for Java-capable phones that aren't necessarily "smart." Check the Facebook blog to see if your phone is one of the 2,500 that can use this app.
Now that you're in, let's check out what you can do (answer: almost anything).