Can someone explain KID?

I know that KID is a defence designed to lure the opponent into setting up his nice cozy center before attacking it - a hypermodern opening. However, to my knowledge, the knight is blocking the bishop from attacking much.

The Wikipedia page says that Black can challenge White's center with e5 or c5, but I don't understand how moving the knight and fianchettoing the bishop helps anything.

Possibly helpful: Starting Out: The King's Indian by Joe Gallagher (2002)

https://web.archive.org/web/20140627055734/http://www.chesscafe.com/text/hansen38.pdf

The answer is in the question: move the knight. How to move it? pick it up with your fingers and put it on a square where you simply don't lose it, or a pawn, by doing so.

Problem solved.

However, I would clearly not advise a beginner to study the KID first.

Anyone who wants to master the King's Indian Defense must dedicate 5 years of his life atop a mountain, eyes stuck on games played by Fischer, Kasparov, Sax or Radjabov, whispering variations and tactical combinations like crazy.

More or less. If you live on a island without mountain, find a cave, it also works. Good luck.

You could also lock yourself in the bathroom and sit in the toilet for 5 years.  I do recommend wiping and flushing occasionally!

Should I use Queen's Indian or Nimzo-Indian instead? Are they just as complex as the KID?

Pete Tamburro suggested Nimzo stuff in Openings for Amateurs. Seirawan suggested KID in Winning Chess Openings. John Watson suggested 1 d4 d5 2 c4 e6 in Mastering the Chess Openings, Volume 4. I think the Watson suggestion is the most common suggestion for those near the beginning of their chess carreers (along with not spending too much time on opening study generally).

I think beginners like the opening because it feels totally safe during the first 5 moves, and you can basically play the same first 5 moves no matter what the opponent does.

After that though it's not so easy.

Comparatively something like the queen's gambit seems harder... but is actually much easier to play during the middlegame, and follows classical principals.

Or players that can't find excitement.

instead of switching opening to another when u cannot handle it well, just try to play it better (try to understand why u don't play it well, then fix it. If u can't make this analysis, then a coach or anybody to help would be useful), u will likely improve.

Playing another variations would just remove a problem to create another one...

And for beginner's level, symmetric openings are the best one to improve, they are more easier to understand than KID which needs lots of knowledge and abilities that a beginner doesn't have.

The KID is popular for two reasons, mainly:

1. It was the opening Fischer used to employ.

2. Many people think that Black gets a kingside attack on autopilot.

1) is true, but very few people have the knowledge to play something remotely reminiscent of Fischer chess- requires huge knowledge about the game, and exquisite positional understanding.

2) is completely wrong- these positions only occur in one pawn structure out of more than one dozen that are important to know if you employ the KID.

In short, I agree: you should really start with something simpler, and easier to understand. The QGD sounds like a very nice suggestion. The usual argument that "it blocks the c8 bishop" just shows limited understanding... else how one would explain what the "smothered" g7 bishop is doing in several KID lines?

The Kings Indian Defence is probably the richest and most complex reply to 1.d4, even top-level GMs can't memorise all the main lines.

Fischer and Kasparov both adopted it as their favoured weapon and look what happened to them, both ended up going completely bonkers...

Good point, well made.

Still bonkers though