In 2004, e-commerce sales totaled an estimated $69.2 billion, according to the U.S. Department of Commerce. That figure is a 23.5% increase from 2003 and represents about 2% of total sales in the United States.

(However, total sales in 2004 increased only 7.8% from 2003, so e-commerce is growing relatively more quickly. This is the same pattern we saw in advertising revenue: relatively rapid online growth, but still only a fairly small proportion of the "offline" industry.)

Most online consumers -- nearly 60% -- begin their shopping searches on aggregator sites such as search engines or auction sites, rather than at sites maintained by individual merchants, according to an article on clickz.com.

The medium's ability to allow easy price comparisons apparently is a driving force. The most popular price-comparison shopping categories are books and clothing.

The most searched-for individual brands are electronics and clothing companies, including Sony, Panasonic, Nike and Ralph Lauren.

About a third of online shoppers said they buy the same brand "most of the time" when shopping online; nearly twice as many say they buy the same brand "some of the time."

The ability to save time is a major motivation for online shoppers.

Surveys conducted before the all-important holiday season in 2004 indicated more than three-quarters of online shoppers like it because it saves them time. Other important factors were better prices (51% of respondents), greater selection (43%) and greater convenience (40%).

Many people apparently comparison shop online, then do their actual buying offline.

And the value of those who search online but convert offline is quite high. A recent study found for every dollar spent online, the average Web-to-store (W2S) shopper spends $1.60 offline at local retailers. The study says W2S shoppers purchase an average of five products, with a median price total of $400, at local stores after researching products online.

Other online commercial sectors also are growing.

For example, 53 million people, or 44% of Internet users and one-quarter of all U.S. adults, now say they use online banking, according to a February 2005 report from the Pew Internet & American Life Project.

That's an increase of 47% from late 2002. Of all the major Internet activities tracked by the Project since its inaugural survey in March 2000, online banking has grown the fastest.

Internet users with high-speed connections, those with six or more years of experience, and those between 28 and 39 years old are the most likely to bank online.