According to wikipedia:
Döner kebab (Turkish: döner kebap or döner kebabı, literally "rotating roast", often abbreviated as döner, also spelled donair, donar, doner, or sometimes donner), is a Turkish dish made of lamb meat cooked on a vertical spit and sliced off to order. Two similar dishes are called shawarma in Arabic and gyros in Greek,[2] although ingredients and sauces differ. In English, the term kebab in some countries refers specifically to döner kebab.
There are many variants in the composition of the meat, the ways of serving it, and the garnishes.