There’s only been 2 intros for The Simpsons with numerous couch gags.
1 old school intro that only lasted the first season, and the 2nd intro which has lasted 19 seasons. (not including The Simpsons Movie intro, and the first episode back from the movie in Season 19)
Now midway through the 20th season, The Simpsons get a whole new HD intro.
Check it out. It’s pretty much a tribute to the last 20 years.