Genotype can be said as the complete set of heritable genes which are capable of being transferred to the offspring from its parents.
The genotype of an individual is determined by two sets of genes: a paternal (carried by the sperm) and a maternal (carried by the egg).
The fusion of the two gametes leads to the combination and permutation of the two sets of each of the 23 pairs of chromosomes, resulting in the genotype of the offspring.