Ovulation is a part of the menstrual cycle, it occurs when an egg is released from your ovary. When the egg is released, it may or may not be fertilized by sperm. If fertilized, the egg may travel to the uterus and implant to develop into a pregnancy. If left unfertilized, the egg disintegrates, and the uterine lining is shed during your period.
See video on Ovulation: https://www.youtube.com/watch?v=nLmg4wSHdxQ