What is the purpose of ovulation

Ovulation is one part of the female menstrual cycle whereby a mature ovarian follicle discharges an egg. it is during this process that the egg travels down the fallopian tube where it may be met by a sperma and become fertilised.

so basically that process is what makes you able to become pregnant.

Ovulation occurs when an egg moves from the ovaries into the fallopian tubes and is ready for fertilization. It occurs midway in a woman's menstrual cycle, but the timing varies for each woman.