Contraceptives are tools and medicines designed to prevent pregnancy. Barrier contraceptives, such as condoms, are designed to prevent the spread of sexually transmitted infections (STIs) as well as prevent pregnancy.
There are "safe days" to have unprotected sex
You should still have sex if the condom is torn
If you point your partners head north that reduces the chance of pregnancy
If you douche with apricot/tomato juice that kills the sperm before you become pregnant
Shoving alligator dung up the vagina after sex kills the sperm
These, and many more you've heard, AREN'T TRUE. The best way to avoid pregnancy and STIs is to use birth control or abstinence.