Almost every culture has its own version of 'fast food', and in Greece that honor goes to the gyro sandwich. A gyro sandwich (pronounced YEER-oh) consists of various rotisseried meats, salad vegetables such as tomatoes, lettuce and onions, along with a yogurt-based tzatziki sauce. These ingredients are placed on a hearty form of grilled pita bread and served as a wrap sandwich. In some countries, a gyro sandwich may also contain french fries or mustard. The type of pita bread may also vary, from the pocket style to a greasier round flatbread.

The meats used in a traditional gyro sandwich may be pork, chicken, beef or lamb. In Greece and surrounding countries, the term gyro sandwich may also refer to a similar sandwich called souvlaki. Greek restaurants in other countries tend to define gyro meat as a mixture of minced beef and lamb, while souvlaki is generally considered a marinated pork product. The lamb and/or beef used in a gyro sandwich is often pressed into a conical shape, then placed vertically on a spit rod for roasting. Gyro sandwich makers will periodically shave off generous portions of this meat and sear it on a grill.

The grilled gyro meat is then placed on a round piece of warmed or grilled pita bread. A traditional gyro sandwich sold in places other than Greece is notoriously oversized. Gyro sandwich makers then add various ingredients, typically a leaf of lettuce, chopped tomatoes and sliced onions. Some makers add french fries at this point. The final step is the addition of tzatziki sauce, which is made with Greek-style yogurt, diced cucumbers, dill weed and a small amount of vinegar. The ingredients of a gyro sandwich are intended to work together, with the tzatziki sauce counteracting the spiciness of the gyro meat.

Because a gyro sandwich can be prepared quickly with only a few ingredients, it has become a popular item on street vendors' menus. Many people encounter their first gyro sandwich at county fairs and other special events. Some grocery stores even offer sliced gyro meat in their deli meat section, or offer kits containing the meat, sauce and pita bread. Gyro meat has also become a popular alternative to the traditional pizza toppings, especially in cities with a large Greek population.