What's the difference between the base (primer???) and foundation?

Primer is used to even skin tone, minimize fine lines and wrinkles, and help give a good base to apply your makeup. While it can be used under foundation, it also can be used alone.

Some primers aren't even a color that you are adding; they are a creme that you are applying to your skin to fix small problems in your face. This is why there are men out there that use primers after shaving; it moisturizes and soothes skin, evening out skin tone, lines, and wrinkles. You just won't ever get them to admit it :-)

When used under foundation, it gives you a good base to apply the makeup on. Your makeup will last longer, run less, and look more even than when applied to the skin alone. They make special primers for eyes and lips, too.

It may sound like a heavy finished look, but when I've had it on, I can't tell the difference in thickness. I can, however, tell a difference in how my makeup feels, how long it lasts, and I don't notice as many small imperfections when I'm done. When I'm going somewhere nice, I use it for a better look, and longer lasting makeup. I don't use it all the time though, too much work.

In simple terms -- like a primer for a wall. The foundation will look smoother and last longer. Personnally other then special occasions or photography -- I don't see a need for it on a daily basis.

i thought woman's just use those things..