So What Are The 'Four Agreements'

I have referenced the Four Agreements a few times, so for those of you who don't know, they come from a book titled The Four Agreements written by Don Miguel Ruiz. They are basic and how I try my best to live. They are the same basic teachings from so many, Christ & Buddha included. The Four Agreements keep you honest, safe, happy, and functional:

1. Be Impeccable With Your Word
2. Don't Take Anything Personally
3. Don't Make Assumptions
4. Always Do Your Best