Phishing, it something may happens to you all the time. When you open your junk mail box, when you see someone said, "Congraduations! You won a price" or something like, "Hi, there, long time no see", and the person sent u a link for you to sign in or fill some personal information. This is consider "Phishing". The word Phishing is from "fishing". And, Refering to Longman Dictionary Online, Phishing mean, "The criminal activity of sending emails or having a website that is intended to trick someone into giving away information such as their bank account number or their computer password. This information is then used to get money or goods."
So, what will you do when you receive a e-mail from email@example.com, asking you to renew personal password with VISA card number, when you do have an account in Royal Bank of Canada? Would you go to the page they sent you and fill in every thing? I wouldn't. First there is no such site as "www.rbc.on.ca" and if RBC do send you a e-mail, they wouldn't send you with an e-mail with user name "admin". Even if they do ask you, they will never ask you to provide VISA card number, which is something they know already. If they have concern about your login password, they will ask you to call them or they will contact you by phone without asking you the password on the phone.
This is the easiest way to avoid phishing, and the best way to do. A lot of website would show you how to anti-phishing. Some suggest people should be educated in school about phishing. Some suggest using e-mail filtering, anti-spam. But I believe the best way is common sense. Phishing is not only exist in cyber world. It also exist in the real every day. Unkown salesman knocking at your day, some unknow air-mail form claim that your far-uncle died and left you few million dollars, someone claims that he's from Rogers and called you about a discount if you could your account with your VISA right now. They are phishing also.
All we have to do is open our eyes, think clear and not to trust any one... beside someone you love. ;-)
Paypal - Protect Your Self
Wikipedia - Phishing
University of Colorado At Boulder - IT Security Topic - Phishing
Longman Dictionary of Contemporary English