The <ahref="licenses/mit">MIT License</a> is a permissive license that is short and to the point. It lets people do anything they want with your code as long as they provide attribution back to you and don’t hold you liable.
The <ahref="licenses/apache/">Apache License</a> is a permissive license similar to the MIT License, but also provides an express grant of patent rights from the contributor to the recipient.
The GPL (<ahref="licenses/gpl-v2">V2</a> or <ahref="licenses/gpl-v3">V3</a>) is a copyleft license that requires that people who modify your code disclose their changes when they distribute their program that includes your code. V3 is similar to V2, but adds a restriction restricting use in hardware that forbids software alterations.