In table tennis, a legal serve that touches the net and still lands correctly is called a let.
A let occurs when a served ball touches the net assembly but otherwise meets the service requirements, including bouncing on the server’s side and then on the receiver’s side. The rally is stopped and the server serves again, with no point awarded.
This is different from a fault. A serve is a fault if, for example, it fails to land in the correct court, is hidden, or is not released and struck according to the service rules. A ball that touches the net during an ordinary rally is not automatically a let; play continues unless another rule requires a stoppage.
In doubles, the serve must also travel diagonally from the server’s right half-court to the receiver’s right half-court. The net-contact rule applies there as well, provided the serve is otherwise legal.