The history of Porky Pig is what this short featurette is all about. It's part of the Looney Tunes Golden Collection: Volume One, and can be viewed on disc two.
Porky was just one of the ensemble in early cartoon, just one of a group, but people liked him best. "He just stole that show," historian Jerry Beck points out. "They ended up making Porky the star of the (early) Looney Tunes."
From there, famous guys in the business like Tex Avery began doing Porky cartoons in the mid and late '30s, "many of them his best cartoons," according to film critic Leonard Maltin.
Anyway, there is a bunch of information packed in this short feature and all of it's pretty interesting.