Orthogonal polynomial

sniffer
i am still learning mathematical physics.

i am learning orthogonal polynomials, but still confused.

what is the meaning of "orthogonal" here?

$$\left<f,g\right>= \int_0^1 f(x) g(x) dx$$
Now f and g are orthogonal $$\iff \left<f,g\right>=0$$.