The current (5th) Generation Toyota 4Runner comes with an arsenal of off-roading tools to help you conquer the trail. Some of them can be confusing, but they're all pretty simple systems to understand. Here's a video showing what they do and how they work. The best thing you can possibly do is to get out there and try them yourself. I hope this teaches you about A-TRAC, the E-Locker, Multi Terrain Select, Crawl Control, and how to use them all.