Phishing is a scam in which the attacker sends an email purporting to be from a valid financial or eCommerce provider. The email often uses fear tactics in an effort to entice the intended victim into visiting a fraudulent website. Once on the website, which generally looks and feels much like the valid eCommerce/banking site, the victim is instructed to login to their account and enter sensitive financial information such as their bank PIN number, their Social Security number, mother's maiden name, etc. This information is then surreptitiously sent to the attacker who then uses it to engage in credit card and bank fraud - or outright identity theft.
Many of these phishing email appear to be quite legitimate. Don't be a victim. Look over the following examples of phishing scams to familiarize yourself with the clever techniques used.