If derivatives are the Justice League of calculus, indefinite integrals are the Anti-Justice League. Indefinite integrals are the antithesis of derivatives—they represent the exact opposite operation. The term antiderivative means the same thing as an indefinite integral...it's like they're Two-Face/Harvey Dent.
It's important to point out the difference between definite and indefinite integrals. Since definite integrals represent an area, they give an actual number. Indefinite integrals, on the other hand, are infinite collections of functions. If the infinite part makes you feel like Superman + Kryptonite, all we're talking about is the + C that gets added to the end of the antiderivative. The constant C can be any number, so there are infinitely many choices. Read on to see what we mean, and you'll feel super once again.