This paper contains a brief review of orthogonal polynomials in two and several variables. It supplements
the Koornwinder survey [40]. Several recently discovered systems of orthogonal polynomials have been
treated in this work. We did not provide any proofs of the theorem presented here but references to
the original sources are given for the benefit of the interested reader. It is hoped that collecting these
scattered results in one place will make them accessible for the user.