Turn on the TV at any time in Japan, and you're likely to come face-to-face with its many unique styles of comedy. While most Japanese comedy is fairly incomprehensible unless your Japanese listening skills are good enough to catch its bullet train-speed jokes, you can always find comedians making funny faces, getting thrown into a freezing swimming pool, or getting hit hard in the crotch when they can't say tongue twisters.
Owarai
The word for comedy of all shapes and sizes in Japan is owarai (お笑い). This refers to comedy that's on television, as opposed to live comedy that's done in traditional theaters, which is called yose (寄席). For the most part, owarai refers to variety shows that feature various types of comedy acts.
A typical variety show will have a bunch of different kona (コーナー– segments, after English 'corner'). These include comedy routines, quizzes, physical challenges, music (live or karaoke), short documentary-style video segments, and segments where everybody eats.
Manzai
Manzai (漫才) is a style of stand-up comedy where two people stand in front of an old-timey microphone and tell jokes (some groups have more than two). One comedian is the straight man/woman (突っ込み) while the other is the silly goofball that says hilarious things (ぼけ), to which the straight one replies with slaps to the head. The meat and potatoes of manzai are gags that consist of comical misunderstandings, double meanings, and dajare (ダジャレ - puns), all delivered at lightning-fast speed. Many groups take their name from food items or oddly Japanized English words.
Konto
Konto (コント – from the French conte) groups do short sketches that revolve around a comical story, weird situation, or strange encounter. A sketch can be as short as two lines or as long as about three minutes. What most sketches have in common is that they're utterly bizarre.
Konto is actually a sub-genre of manzai, but there are some major differences. Unlike manzai, konto can have props, special effects, a stage set-up, music, video, etc. If your Japanese skills aren't up to par, you can still watch konto and get most of the wacky slapstick humor or straight-up bizarreness.
Rakugo
Rakugo (落語) is a traditional type of comedic storytelling. It should have a blog post all for itself because there's quite a bit to it. In rakugo, the storyteller sits in a kimono with his legs tucked under him and tells story. The name literally means something like 'story with a punch line.' Not all rakugo stories are jokes; some are simply stories. The humor and stories of rakugo generally appeal to an older, more conservative audience.
What's amazing to me about rakugo is that there are old stories that have been passed down from the Edo Period. I can't think of any American or British comedy that's been passed down that long and is still funny. Even Monty Python is only about forty years old.
The Owarai boom
Right now, Japan is experiencing an 'owarai boom.' New comedians come and go as quickly as 5-hour-old sushi at a grocery store taimu saabisu (タイムサービス- time service, or the end of the day when everything is marked down). In a society that's pathologically stressed out, there's nothing like a good gut laugh to make everything alright.