After being on and off for years, tennis was introduced as a full medal sport in 1988.

Rugby has only been a sport at five Olympic games, and Rio will be its first appearance as a medal sport since 1924!

Lacrosse was included in 1904 and 1908, but not since!

It was only introduced in 2008, but it's definitely a sport!

It hasn't been in the Olympics since 1936.

It's been a regular medal sport since 1992!

It was included once, back in 1992, but hasn't been seen since.

Probably a bit too fancy for the Olympics, huh? It was included in 1900, but not since.

Golf is making a comeback for the Rio Olympics, 112 years since the last time it was included as a sport.

While men do a decathlon with 10 events, women do a heptathlon with only seven. Because women aren't strong enough to do 10, obviously.

It's real! And oh boy, it's fun to watch.

Racewalking is real, and is competed as a 20km event and a 50km event.

Believe it or not, tug of war was a real sport between 1900-1920.

Baseball was voted out of the Olympic games after 2008, though it was recently announced it'll be coming back for the 2020 games in Tokyo.

Taekwondo has been a full medal sport since 2000.