It is a prefabricated restaurant building characteristic of American life.
However, I'd like to make some attempt here to define (or perhaps interpret) what a diner is. For one thing, there are a number of characteristics which many diners share. Most are open 24 hours a day, or at least extremely late, and serve breakfast for the whole time. Most serve coffee (black as death) as a staple. Another typical characteristic is one of several themes: Hellenic, Neon '50's, or Abandoned Train Car. The former is usually a restaurant which is open late (if not 24 hours), which caters to the old folks, or the high school kids, and, late at night, to the worst elements (such as my friends). The latter, however, is what the purists idealize when they talk of diners. A diner is a prefabricated restaurant building characteristic of American life, especially in New Jersey, Pennsylvania, New York, and in other areas of the Northeastern United States, as well as in the Midwest, although examples can be found throughout the United States, Canada, and parts of Western Europe. In many areas, diners were superseded in the 1970s by fast food restaurants, but in parts of New Jersey, New York, the New England states, Delaware and Pennsylvania the independently-owned diner remains relatively common. Yeah, let's leave in like 15 minutes. This is how most diner nights started for us. We both have something to talk about. It's best talked about over coffee. It's more fun if we can entertain each other with diner tricks. It can only be handled in a diner. It doesn't need to be a specific diner. Just any diner in New Jersey. Hop in the car. Drive around Dinner usually refers to the most significant and important meal of the day, which can be the noon or the evening meal. However, the term dinner can have many different meanings depending on the culture; it may mean a meal of any size eaten at any time of day. Historically, it referred to the first meal of the day, eaten around noon, and is still sometimes used for a noontime meal, particularly if it is a large or main meal. The first diner was created in 1872, by a man named Walter Scott. He decided to sell food out of a horse-pulled wagon to employees of the Providence Journal, in Providence, Rhode Island. Scott's diner can be considered the first diner with “walk up” windows that were located on each side of the wagon. In many areas, diners were superseded in the 1970s by fast food restaurants, but in parts of New Jersey, New York, the New England states, Delaware and Pennsylvania the independently-owned diner remains relatively common. Diner manufacturing suffered with other industries in the Depression, though not as much as others, and the diner offered a less expensive way of getting into the restaurant business as well as less expensive food than more formal establishments. In many areas, diners were superseded in the 1970s by fast food restaurants, but in parts of New Jersey, New York, the New England states, Delaware and Pennsylvania the independently-owned diner remains relatively common. Obviously, the classical definition of a prefabricated restaurant with counter service that is hauled out to a remote location still works, but the question is, with that sort of structure vanishing from the American landscape, has the definition evolved? What is the diference between a dive, a joint and a diner?  The first is that diners can be roughly divided into two type: The Suburban, and the Highway. The former is usually a restaurant which is open late (if not 24 hours), which caters to the old folks, or the high school kids, and, late at night, to the worst elements (such as my friends). The latter, however, is what the purists idealize when they talk of diners. These 10 animal facts will amaze you. A diner is a type of American restaurant. It generally offers typical American fare, includes seating at a communal counter and frequently operates 24 hours per day. Dating from the late 1800s, the diner's popularity peaked between the mid-1930s and the mid 1960s. One major feature of a diner is the style and type of food. Many diners serve a variety of breakfast foods at any hour of the day. Common fare includes scrambled eggs, pancakes, burgers, sandwiches, pie and the like.
http://www.physics.drexel.edu/~goldberg/princeton/def.html https://en.wikipedia.org/wiki/Diner http://www.njdiners.com/whatsadiner.htm https://en.wikipedia.org/wiki/Dinner https://en.wikipedia.org/wiki/Diner https://en.wikipedia.org/wiki/Diner http://www.chowhound.com/post/definition-diner-287255 http://www.physics.drexel.edu/~goldberg/princeton/def.html http://www.wisegeek.com/what-is-a-diner.htm
what is a diner