categorisation vs assortment

categorisation and assortment both are nouns.

Word	Noun	Adjective	Verb	Adverb
categorisation	Yes	No	No	No
assortment	Yes	No	No	No

As nouns, categorisation and assortment are synonyms defined as:

categorisation and assortment: the act of distributing things into classes or categories of the same type

Other synonyms of categorisation include categorization, classification, compartmentalisation, compartmentalization.

categorisation (noun)	assortment (noun)
the act of distributing things into classes or categories of the same type	the act of distributing things into classes or categories of the same type
the basic cognitive process of arranging into classes or categories	a collection containing a variety of sorts of things
a group of people or things arranged by class or category