What is meant by Cascading?

[Chandaka Anil Kumar]

Without Comparing with Mulitilevel Cascading

[Nic Brough -Adaptavist-]

It means the value in one part of a field "cascades" down into limiting the list in another.

Country/region is an example - the value USA in one field would limit the region list to the 50 states, but if you selected UK, you would probably find either England/Northern Ireland/Scotland/Wales (and then possibly protectorates and territories), or the list of English, Scottish, Welsh and Northern Irish counties.