How to root android phone:

iPhone links:

Some apps for rooting: Towelroot, Kingoroot, and others. All-important unrooting also discussed:

http://www.digitaltrends.com/mobile/how-to-root-android/3/
http://www.digitaltrends.com/mobile/how-to-root-android/4/

From the google search 'how to root android'

A great article that oddly breaks down rooting by phone brand:

http://m.androidcentral.com/root