Don't look now, but Thanksgiving is bearing down upon us, which you probably know means that the biggest shopping weekend of the year is right around the corner. What you might not know, however, is that the Monday following that weekend, is fast becoming the biggest online shopping day of the year. This year, online retailers plan to help drive Cyber Monday shopping with special promotions and discounts, with deals ranging from free shipping to gifts with purchase to percentages off, according to an eHoliday Mood Study.
—Patricia Keefe, "Ready, Set, Shop!," InformationWeek, November 22, 2005

Experts cite two reasons for the Cyber Monday phenomenon: People are shopping online at work, where they have faster Internet connections, or they're unable to finish their shopping during the Thanksgiving holiday and need a spill-over day.
—Sandra Guy, "Cyber Monday gaining ground," Chicago Sun-Times, November 21, 2005

Because the world needs another Officially Named shopping day, the people who dreamed up Black Friday (the day after Thanksgiving, when retailers hope to turn a profit) have created a nickname for the following Monday.

Hence the catchy Cyber Monday, so called because millions of productive Americans, fresh off a weekend at the mall, are expected to return to work and their high-speed Internet connections on Nov. 28 and spend the day buying what they liked in all those stores.

Though it sounds like slick marketing, Cyber Monday, it turns out, is a legitimate trend. According to Shop.org, a trade group, 77 percent of online retailers reported a substantial sales increase on the Monday after Thanksgiving last year.
—Michael Barbaro, "Ready, Aim, Shop," The New York Times, November 19, 2005