An overview of the basic results on Macdonald(-Koornwinder) polynomials and
double affine Hecke algebras is given. We develop the theory in such a way that
it naturally encompasses all known cases. Among the basic properties of the
Macdonald polynomials we treat are the quadratic norm formulas, duality and the
evaluation formulas. This text is a provisional version of a chapter on
Macdonald polynomials for volume 5 of the Askey-Bateman project, entitled
"Multivariable special functions".