The philidor defense

The philidor-defense is a very important endgame to learn. If your opponent has a rook and a pawn and you only have a rook, you can draw the game with the philidor defense. The position of the philidor defense is this:

If it's this position, keep your rook on the 3rd rank untill white moves its pawn. Then you'll begin to attack the king by going to the 1st rank.

The game ends drawn and you saved the game. Also mke sure you keep your king in front of the pawn.