  $W$-algebras are certain algebraic structures associated to a finite
dimensional Lie algebra $\mathfrak g$ and a nilpotent element $f$ via
Hamiltonian reduction. In this note we give a review of a recent approach to
the study of (classical affine and quantum finite) $W$-algebras based on the
notion of Lax type operators. For a finite dimensional representation of
$\mathfrak g$ a Lax type operator for $W$-algebras is constructed using the
theory of generalized quasideterminants. This operator carries several pieces
of information about the structure and properties of the $W$-algebras and shows
the deep connection of the theory of $W$-algebras with Yangians and integrable
Hamiltonian hierarchies of Lax type equations.
