  We describe a grading switching for arbitrary non-associative algebras of
prime characteristic p, aimed at producing a new grading of an algebra from a
given one. This is inspired by a fundamental tool in the classification theory
of modular Lie algebras known as toral switching, which relies on a delicate
adaptation of the exponential of a derivation. We trace the development of
grading switching, from an early version based on taking the Artin-Hasse
exponential of a nilpotent derivation, to a more general version which uses
certain generalized Laguerre polynomials playing the role of generalized
exponentials. Both versions depend on the existence of appropriate analogues of
the functional equation exp(x).exp(y)=exp(x+y) for the classical exponential.
