You know those annoying emails that pretend to be from PayPal, EBay or the local bank, asking you to login to your account and validate your password or other credentials? Those are "phishing" attacks – you've officially been "phished".
According to Wikipedia: "Phishing is the criminally fraudulent process attempting to acquire sensitive information such as usernames, passwords and credit card details by masquerading as a trustworthy entity in an electronic communication. Phishing is typically done via email or instant messaging and directs you to enter details at a fake website that usually is almost identical to the legitimate one.
Read more about phishing on Wikipedia.org