The message
from Dave contains these words:

I thought caulk was a quick fix for small gaps. Are you saying that
there are two types of caulk, depending on the end usage?

As I use it, caulk comes in tubes for a skeleton gun and is for things
like gaps between skirtings and unevenesses in walls, down the edges of
fitted units, that sort of thing. Stays slightly flexible and is very
very sticky so it doesn't come adrift and expose a gap just where you
were hoping to hide one.

Filler is for filling dents and things, perhaps sloppily made joints
which aren't expected to move slightly, that sort of thing.

Filler you trowel on and sand down. Caulk you get right while it's wet,
using a wet finger if needed.

Filler is (often) plaster based, caulk is PVA based.

--
Skipweasel
Pay no attention to that man behind the curtain.