PHP - hide url (GET) parameters

Question

I have a link in my PHP/HTML like this:

Answer 1

A login should be done via POST, not GET. Furthermore, sensitive details should be sent via HTTPS.

The process of creating secure login functionality could have an entire book written about it, so I suggest you start out by reading the definitive guide to web-based forms authentication.

If you have further specific questions about security, I suggest you try over at Security.SE.