cool 👍
j

In the opening phase, you typically want to get your king to safety and connect your rooks on the back rank. Castling helps with both of these things so it is a very useful move.
Will add that in closed positions with the Queens off the board, it is often times preferable to leave the king in the center both for attacking chances and king safety

If you don't castle, then your opponent will. Then, you'll get mated since your king is trapped in the center.

I think you should mostly castle on King side, unless your opponent makes it difficult, then castle on the Queen's side, but don't try to castle on the Queen's side always, just only if it's difficult or risky to castle on the King's side. I get opponents who attack my King side before I've castled.
Depends what you mean by early, as soon as possible before developing any other pieces? Or see which side your opponent is going first, it can be an advantage to leave him/her guessing?

I have play just over 200 games. One of my most recent games was a game in which I did not castle. I think that was a first. Up until then I have always castled. The post game analysis showed there were only two times when the best move was to castle, and it was only slightly better. A very strange game (and a win) . . .
In a chess 960 game, I actually castled on my second move! Again, very strange.
Protect the King in a corner and get the Rook out, generally very good advice.
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