The haploid number of chromosomes in humans is 23. This means that each human cell contains two sets of 23 chromosomes, one inherited from the mother and one from the father. When the egg and sperm combine during fertilization, the resulting zygote has a full complement of 46 chromosomes, which are later halved during the formation of gametes (sperm or egg cells) so that each gamete carries only 23 chromosomes. This number is important for genetic diversity and helps to ensure that offspring have a unique combination of genes from both parents.