“direct navigation,” when people go into the browser url bar and type in what they’re looking for and just add “.com” to the end like “weddingshoes” and then add “.com” — according to source 10 below, millions do it [1]

tasting, Tasting takes advantage of a provision that allows domain-name buyers a free five-day trial period. Intended to protect customers who mistakenly purchase the wrong name, it handed aggressive domainers another means with which to expand — and exploit — their portfolios. [1]

“typo-squatting,” it’s a practice now coming under the same intense scrutiny long faced by cybersquatters. Microsoft (Charts, Fortune 500) and Neiman Marcus are just two companies whose lawyers have brought anti-cybersquatting lawsuits, charging domainers with intentionally profiting from variations of their trademarks. [1]

Cybersquatting, according to the United States federal law known as the Anti-Cybersquatting Consumer Protection Act, is registering, trafficking in, or using a domain name with bad-faith intent to profit from the goodwill of a trademark belonging to someone else. The cybersquatter then offers to sell the domain to the person or company who owns a trademark contained within the name at an inflated price. [2]

parking, the main way that domainers make money: they fill their undeveloped domains with relevant pay-per-click ads that throw into their pockets steady cash [1]

Sources:
1. http://money.cnn.com/magazines/business2/business2_archive/2007/06/01/100050989/index.htm
2. http://en.wikipedia.org/wiki/Cyber_squatting