Universal set is the total collection of all possible solutions to a consumer problem (for example, the total number of brands of deodorant available on the market)
Awareness set includes, quite simply, the set of brands or alternatives of which a consumer is aware.
The consideration set of customers in order to learn about the total number of brands, or alternatives, that are considered in consumer decision making.
The inept set: alternatives in the awareness set that are deemed to be unacceptable for further consideration.
The inert set: alternatives in the awareness set about which consumers are indifferent or do not hold strong feelings