Yo mama or Chuck Norris jokes-which was the best?

anyone know when and how the Chuck Norris jokes started?

And why him?

He's more known for these jokes than his movies (which were mostly of the straight to video, bargain bin variety)
I looked up this topic the other day and meant to paste here, but forgot. Maybe this is true, maybe it's not. Only Chuck Norris knows for sure.

https://www.quora.com/Where-did-the-Chuck-Norris-joke-phenomena-originate-from
The Chuck Norris jokes started in the summer of 2005 as the result of a thread on the SomethingAwful forums. A thread started called “Post Your Vin Diesel Facts” in response to the movie "The Pacifier" coming out. This movie featured Vin Diesel as a Navy SEAL turned babysitter. After the thread died out a teenager named Ian Spector decided to make a web page called the "Vin Diesel Fact Generator" to be a repository for the "facts" and allow visitors to make new "facts". The web site had some popularity but started to die out by the summer, so Spector solicited suggestions for a replacement for Vin Diesel. Norris was the winner by an overwhelming margin on write-in votes. This was possibly because of the "Walker Texas Ranger lever" joke which Conan O'Brien was running on the Tonight Show at the same time. As a result Spector changed the "Vin Diesel Fact Generator" into the "Chuck Norris Fact Generator" which you can visit at Chuck Norris Facts and the rest was history. The new generator debuted in December of 2005 and was just a one-pager with an email address to make submissions.