Gary Gygax was a pioneer in creating fantasy games with wizards, goblins, and elves, such as Dungeons & Dragons. He introduced Dungeons & Dragons in 1974 and an estimated 20 million people have played the game since. The fantasy game became a cultural phenomenon, students selling about $1 billion in books and equipment. Dungeons & Dragons was originally targeted to college-age, but it quickly became popular with younger generations, and eventually was developed into a computer game.