(Note: I'm the author, but have nothing to do with the Open API Initiative)
Swagger 2 (current version) got really popular the past few months as a way to document your API. Now, Swagger 3 (er, Open API Spec 3 as it's now known) is about to launch. I had a hard time finding what was new, so we made an example-filled guide that will help with your migrations.
tl;dr: Swagger 3 isn't ready for use yet, and is way more complex but solves a lot of problems with 2.
Swagger 2 (current version) got really popular the past few months as a way to document your API. Now, Swagger 3 (er, Open API Spec 3 as it's now known) is about to launch. I had a hard time finding what was new, so we made an example-filled guide that will help with your migrations.
tl;dr: Swagger 3 isn't ready for use yet, and is way more complex but solves a lot of problems with 2.