What is a "child forum"?

I notice in the search there is a “search child forums”. What are they?

A child forum is one that branches off from a main forum.

A possible child forum for GQ might be CQ (computer questions). One for Great Debates might be Political Debates.

The SDMB doesn’t have any child forums (as far as I know)

Lobsang describes it precisely. Other boards I participate on have such forums. For example, on the Pizza Parlor any discussion that the OP wishes to be kept to members over 18 goes in “the Beverage Bar” – and there’s a child forum under that for sexual topics, called, amusingly, “Sex Talk with the Church Lady.”

So, sort of like a subdirectory, then?

Spot on.

(some more characters for the 10ch limit. When will that be sorted btw?)

I know that it’s being used in a technical sense, and not a real one, but somehow having a sex discussion in a child forum just seems… wrong, somehow.

With the church lady no less.

Type in a few extra spaces. They count as characters.