When the tennis ball from a service touches the net but still lands within the service box. The server gets another try as this does not count as a fault.

A first or second serve that nicks the net and lands in is called a let. The serve must be taken over. There is no limit to how many lets a server can have in a point. A let is also the term used when an extraneous object interferes with a point, a distraction disturbs play or a player is not ready to receive serve. Either player may call out "let" to stop play.