31、Until a few years ago, vans were commercial vehicles used mostly by business firms as delivery trucks. Today, the van has become a palace on wheels. It is a place where the owner of a van, called vanner, can relax, visit with good friends, eat, drink, sleep and even watch television.
A van may often look like an art museum on wheels. The exterior of vans is a visual feast of colors and styles. Many vans have paintings of various kinds on the sides. Each van is decorated and finished to reflect the personality of its owner. The most luxurious（豪华的）van has TV, a refrigerator and a sink, etc. Some even have paintings on the walls.
Van is very popular with young married couples with small children, and with young people, such as high school and university students. The latter frequently use their vans for traveling parties, often going from place to place, or city to city, gathering friends along the way.
In 1966 there were about 190,000 vans registered in US. By 1976 sales of vans were more than 2 million a year. What is the reason for van boom（快速发展）? Freedom and chance to be with other people are some of most often expressed reasons.