Its pared-down definition is land. The real estate industry, however, is much more complicated than that. It is the buying, selling, renting, leasing, and management of commercial, residential, agricultural, and other kinds of property, including all the functions that support such activity, such as appraising and financing. The successful Realtor is necessarily a shrewd salesperson with a deep knowledge of real estate markets and a broad understanding of the contracts, laws, and tax regulations that apply to real estate transactions.

The source of almost half the privately owned wealth in the U.S., real estate is an industry famous for making people filthy rich and is responsible for over five million jobs in the U.S. The industry is a cyclical one, with booms and busts tied closely to the economy's overall performance. For example, in the late 1980s and early 1990s, the real estate industry struggled through a devastating recession. Today, however, the industry enjoys rising land and property values in most parts of the country, and especially in regions such as Seattle and Silicon Valley, where high-tech research and manufacturing companies are pumping money into the economy and attracting more workers than can be served by existing housing, thus driving up both rents and property values.

In the generally high-flying economy, business finance and services companies are also prosperous, so in the cities where they are centered, such as New York, San Francisco, Los Angeles, Miami, and Dallas, the real-estate markets are healthy.

Finally, with a generation of aging baby boomers set to enter their high-earning years, the residential real estate market should remain steady as well. Still, real estate veterans remain cautious, wary of the type of oversupply that crippled the industry in the late '80s.