Contraception include barrier methods, such as:

condoms
diaphragm

hormonal contraception, also known as oral
contraception, and injectable contraceptives.
Contragestives, also known as post-coital birth control,
include intrauterine devices and what is known as the morning after pill.

The combined oral contraceptive pill, often referred to as the birth-control pill or simply “the Pill”, is a birth control method that includes a combination of an estrogen (oestrogen) and a progestin (progestogen). When taken by mouth every day, these pills inhibit female fertility.
Combined oral contraceptive pills should be taken at the same time each day. If one or more tablets are forgotten for more than 12 hours, contraceptive protection will be reduced. Most brands of combined pills are packaged in one of two different packet sizes, with days marked off for a 28 day cycle. For the 21-pill packet, a pill is consumed daily for three weeks, followed by a week of no pills. For the 28-pill packet, 21 pills are taken, followed by week of placebo or sugar pills. A woman on the pill will have a withdrawal bleed sometime during the placebo week, and is still protected from pregnancy during this week.

Combined oral contraceptive pills were developed …