True stingrays give birth to live, fully formed young. Stingrays tend to give birth to litters of between 5 and 13 "pups". Female stingrays can retain semen from sexual encounters and have been known to give birth at later dates, seemingly at will.
Not all rays are stingrays. Rays are a type of fish known as Chondrichthyes, which are also related to sharks. While stingrays are the most notorious kind of ray, there are many other kinds of rays including devil rays, whiptail rays and eagle rays. Altogether there are approximately 500 species of "rays". A stingray is a type of ray and is distinguishable from other rays by it's deadly stinging spines.