If diners are newly hot, they're surely the oldest new restaurant concept around. According to Richard J.S. Gutman, author of American Diner Then and Now (HarperPerennial), diners began in the 1870s as "night lunch" wagons--horse-drawn carts that served meals to factory workers on the night shift, when regular eateries were closed. Over the decades, these portable dining carts expanded to include indoor seating, began opening for multiple meals (sometimes around the clock), put down roots in fixed locations, and developed the streamlined, stainless-steel-and-tile look people still associate with diners today.
For purists, diners still fit standard criteria. A true diner is prefabricated, manufactured by a specialized diner maker, says Randy Garbin, publisher of Worcester, Massachusetts-based Roadside, a magazine about diners. "The space should be long and narrow, from which you can slice off little bits of intimacy," he adds. "It's that sense of public intimacy that gives diners their distinctive feeling. And there should always, always be a counter."