Answer:
There are two types of twins – identical (monozygotic) and fraternal (dizygotic). To form identical twins, one fertilised egg (ovum) splits and develops two babies with exactly the same genetic information.
Identical twins or triplets happen when a single egg is fertilized and then later splits. These newly divided embryos are identical. Children that are identical multiples will look like each other and be the same sex. Fraternal multiples develop from separate eggs that are fertilized by a different sperm.