Doner started in Turkey in the 1800s. Before then, kebabs had been cooked sideways on flat grills for centuries. The new idea was to stand the meat upright in front of the heat, so the fat dripped down and the outside cooked extra crispy.
Modern doner travelled the world in the 1970s, when Turkish people who moved abroad opened doner shops. In Germany, the doner kebab in a soft bread roll became one of the country's most popular fast foods. In the UK, it became a friendly Friday-night snack. The Turkish recipe is now eaten in almost every country.
Back in Turkey, doner is often served on a plate with rice or thin bread, with salad, yoghurt and sometimes a spoonful of fiery red pepper paste on the side. It is a sit-down meal as often as it is a takeaway. Many Turkish children grow up with doner the way other children grow up with pizza.
Making a really good doner takes practice. The meat has to be layered just right, the flame has to be steady, and the cook has to slice with a long sharp knife at exactly the right angle. The best doner shops are run by people who have been making it for decades.