A grass court is one of the types of tennis court on which the sport of tennis, originally known as "lawn tennis", is played. Grass courts are made of grasses in different compositions depending on the tournament.

A tennis court is the venue where the sport of tennis is played. It is a firm rectangular surface with a low net stretched across the centre. The same surface can be used to play both doubles and singles matches. A variety of surfaces can be used to create a tennis court, each with its own characteristics which affect the playing style of the game.