This article is from the Golf FAQ, by marcelo@nntpserver.Princeton.EDU (Marcelo A. Gallardo) with numerous contributions by others.
What causes it?
+++++++++++++++
For the most part, a hook or a slice is caused by the clubface being
opened or closed upon contact. Most people also tend to agree that an
inside-to-out swing plane causes a hook, and an outside-to-in swing
plane causes a slice.
o = ball x = clubhead path
x
x
o x o x x x o x
x
x
HOOK STRAIGHT SLICE
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