Each person carries 23 pairs of chromosomes in every cell that makes up their body, with the exception of gametes, which contain 23 SINGLE chromosomes. So when a sperm and egg meet, they then have 23 pairs. In the process of meiosis 'crossing-over' occurs, which means that the chromosomes get "shuffled". This means that the child can receive random traits not only from the parents, but also the grandparents. so there is about 2⁴⁶ possible pairings, excluding the risk for things such as Down-Syndrome
for instance in humans, the somatic cells include 46 chromosomes which is the diploid wide variety (2n) and each sperm and egg has 23 chromosomes wherein one of them is the sex chromosome.