Net in Go: How the Geta Capture Works | PlayGo.gg

A position in which you surround a stone or group of stones that leaves room for them to run, but they cannot escape and will eventually be captured.

What is a net?

A net is played one or two points away from the stone you want to capture, on a diagonal that cuts off every escape line at once. The trapped stone still has liberties, often two or three, but every direction it tries to run, the net stone or the surrounding wall is already there to surround it.

Because the trapped stone never has a single forced response, the net isn't a sequence. It's a position. After one move, the capture is guaranteed; the opponent simply can't extend in any direction without making things worse.

When to use a net instead of a ladder?

The Kageyama rule from Lessons in the Fundamentals of Go: try the net first. If a geta works cleanly, prefer it over a ladder for three reasons:

- No ladder breakers. The geta depends only on local stones. A friendly stone of the trapped color, played far away, cannot save the capture. - No long sequence to read. A ladder runs ten or more moves across the board. A net is one move and the result is settled. - Better thickness. The captured stones leave behind a position with more liberties for the capturing wall, often producing stronger outside influence than a thin ladder line.

The trade-off is slightly less efficiency in pure points, since the trapped group keeps a few extra liberties. For most players in most positions, that cost is well worth paying. To check a candidate net, place the stone mentally and trace every possible escape: if each one runs into existing stones or atari, the net works.

Example of a net in a game

How can you net the following stones?

Restricting the opponent's options is enough. You don't always need to touch a stone to kill it. The geta is the cleanest, smallest version of that idea: one stone, one diagonal, and an enemy stone with nowhere left to go.