Proper communications are easy to spot as they'll always say things like, "Dear Mr Shunter", instead of "Dear Sucker". And "...your account number ending .....34".
If you ever get an email from a bank, never click on the link. Go directly to their site by typing the name in a browser. If it's something important, the website will tell you. Incidentally, all the emails I occasionally get from Lloyds TSB never have a clickable link in them, they just say "visit the website". That the right way to do it.