Hello Joanna,
Others may add to or subtract from my comment but the biggest
difference is that a scroll saw moves its blade from both directions,
i.e. the yoke that holds the blade pulls it up and pulls it down. With
a jig saw, the blade is pulled and pushed from a single stem and may-
in the case of some older "scroll saws" use a spring to provide
downward tension.
Also, jig saws are often hand held, except for those held upside down
in a table like I alluded to in my second example above,
Marc

intuitiveart wrote:
So...what's the difference between a scroll saw and a jig saw?

thanks,

Joanna