The board and its squares

A chessboard has 64 squares: 8 files and 8 ranks. The files are lettered a to h, left to right. The ranks are numbered 1 to 8, going up.

A square's name is its letter followed by its number. The bottom-left square is a1. The one above it is a2. The one to the right of a1 is b1.

That is the whole system. Once you can read a square, you can read a whole game, describe a position over the phone, or write your moves down.