Condoms work by trapping sperm and thereby preventing them from entering the vagina and the uterus. They help prevent sexually transmitted diseases by providing a barrier between the skin of the vagina and the skin of the penis and by keeping semen out of your body.
Condoms provide good pregnancy prevention and STD protection if used properly (but can't protect you from exposure to sores or microscopic warts on the testicles or other uncovered parts). They're easy to obtain (except for those who are embarrassed to ask for them at a drugstore counter, which Penelope Hitchcock, chief of the Sexually Transmitted Diseases Branch at the National Institute of Allergy and Infections Diseases, says is a real problem). They're relatively inexpensive, and convenient to carry and to have on hand for unplanned sex. Some women find it quite nice to have the man take responsibility for birth control—a rarity, given the preponderance of female-controlled contraceptives. As soon as you want to get pregnant, stop using condoms; there's no delay in regaining your fertility.
A generic drug is made with the same active ingredients and is available in thesame strength and dosage form as the equivalent brand-name product. Generic drugs produce the same effects in the body as the brand-name drugs, because both contain the identical active ingredients...