What's the difference between concealer and foundation, and do you need both?

I have dark undereyes and pimples(teen) and I only use foundation..But would it also help more if I used concealer? what's the difference between them? and do I need it? help!What's the difference between concealer and foundation, and do you need both?
Foundation is meant to go over your entire face, while concealer is meant to cover blemishes, dark circles, etc. It couldn't hurt to use a concealer for the dark circles. As for your pimples, I would recommend using an astringent daily, and make sure you take your makeup off every night so it doesn't end up in your pores.What's the difference between concealer and foundation, and do you need both?
A concealer is thicker and 1 - 2 shades lighter than your natural skin tone. I'm a beauty consultant and I gave my daughter some of my products--face wash, acne gel, and mineral foundation. She was cleared up in about 4 days. Liquid foundations actually clog pores and do more harm than good. Mineral foundations sit on the surface of your skin rather than get absorbed into the skin.
if you feel like you don't need much coverage that a foundation gives but want to cover certain spots, you should stick to your concealer and also try out a tinted moisturizer which gives you a light coverage and spf coverage





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if the foundation alone isn't workinq , id say to use concealer ! Napoleon concealers are perfect ! honest worth the cash too , and youu can qet like duo's so that you can make your skin tone .
I use to only wear foundation and I also have dark undereyes. But now I use foundation and concealer . and it works for me.
foundation makes skin appear more even toned and concealer hides the stuff you want to hide such as pimples, undereye circles, scarring, etc.