Wal-Mart.com is one of the 10 most popular shopping Web sites, Stores magazine reports.

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Ohmigosh. . .You jump out of bed. It's 3 a.m., and you forgot that your mom's birthday is only three days away. You head over to the computer and start surfing. You scroll through your favorite site. You see a purse, a vase andĀ then you find it -- the perfect pair of earrings. You mother's guaranteed to love them.

You place them in your shopping cart, enter your credit card and shipping information. You click send. In less than an hour, you're all done. And, you didn't have to get dressed or leave the house.

E-commerce, the buying or selling of goods and services over the Internet, is changing the way that we shop. On an increasing basis, consumers turn to the Internet to purchase and research items like dishwashers, cars, stocks, travel and even clothing. According to a September 2007 Pew Internet & American Life Project survey, 49 percent of Americans have bought a product online and 60 percent rely on the Internet to conduct product-related research.

E-commerce's advantages aren't just for consumers; retailers also find there are advantages to selling online. Customers can shop in their own time, and an online store doesn't require live salespeople.

What exactly are e-commerce's advantages for consumers? And, what are those advantages for retailers? Read on to find out.