Sex can be considered "safe" if it avoids the risk of one person infecting another with a sexually transmitted disease (STD). Some individuals and groups maintain that the only sex that is 100 percent safe is no sex—that is, abstinence. But since STDs are usually passed on through bodily fluids (genital herpes is an exception, being transmitted by skin-to-skin contact), any form of sexual expression that avoids one partner's exposure to the body fluids of another can be reasonably described as "safe." Although this definition would include such practices as mutual masturbation (once known as "heavy petting"), the most common contemporary definition of the term "safe sex" involves the use of a latex condom to avoid the spread of STDs; such devices have been shown to be 98-100 percent effective.

Safe sex is a vital necessity in the modern age, and has been so ever since...