Linnaeus gave the first proper classification of organisms into two kingdoms, Plantae and Animalia.
This is called as the two kingdom system of classification.
The major criteria used by him was locomotion, presence or absence of cell wall, mode of nutrition, response to external stimuli, and contractile vacuoles.
Copeland proposed the four kingdom system of classification, with the following four kingdoms:
Monera
Protozoa
Metaphyta (= Plantae)
Metazoa (= Animalia)
Aristotle classified plants and animals based on few, observable, morphological or superficial characters.
Whittaker proposed the five kingdom system of classification. He has used many criteria, like, (i) nature of cell organisation, (ii) life form, (iii) mode of nutrition, (iv) ecological role, and (v) evolutionary trend. The five kingdoms are: