A cup holder is a device, such as a zarf, to hold a cup or other drinking vessel. It may be free standing to hold cups securely on a desk or other flat surface, or in a tree style to store sets of cups in kitchens. They may be built into automobiles or chairs, or fixed to the walls of airplanes, boats, buses and trains. Automobile cup holder The development of the drive-in restaurant was a step in the cup holder's development. Servers would attach a tray that hooked over the car's side window, which needed to be left up a little for it to attach to. This gave a temporary table to hold drinks and food while eating in the car. The drive-in restaurant and cinema encouraged the development of built-in tray tables; often, the inside of the glove compartment lid, when folded down, had indentations to hold cups, cans as well as pistachio shells and were found in cars as early as the 1957 Chevrolet Bel Air. These were sufficient to hold beverages when the car was stopped, but not while in motion. The later development of the drive-through restaurant encouraged the development of better holders for drinks, and a more fast-paced life and longer commute times made many drivers desire to drink their morning coffee in the car on the way to work. The 1960s saw coffee cups with wide, flat, rubberised bases being sold, which would keep them steady on the dash or console. A little later, aftermarket cup holders began to be sold. These often clipped onto the door windows, although other designs wedge in between the front seats and the center console. Built-in cup holders began to be available in the 1920s. Minivans were pioneers in their availability, and they still offer the greatest number of them. Over time, automotive cup holders have become larger and more sophisticated, so that they can hold a variety of different cup sizes securely. Many offer spring-loaded holders that clasp the cup securely, no matter how large or small. The development of ever-larger cups by fast-food chains and convenience stores in the US and Canada has proven a challenge to automotive designers; many fast-food chains now offer 44 fl.oz. (1.3 L) drinks. The automobile cup-holder has also driven the development of "car cups" designed to fit within most cars' cup holders; these have a narrower base but flare