Whats the difference between HTTP and HTTPS?
The "S" in HTTPS indicates a secure site. If you visit a web
site or web page, and look at the address in the web browser, it
will likely begin with the following: http://. This means that the
web site is talking to your browser using the regular 'unsecured'
language. In other If you fill out a form on the web site, someone
might see the information you send to that site. This is why you
never ever enter your credit card number in an http web site! But
if the web address begins with https://, your computer is talking
to the web site in a secure code that no one can eavesdrop on.
If a web site ever asks you to enter your credit card
information, you should look to see if the web address begins with
https://. If it doesn't, there's no way you're going to enter
sensitive information like a credit card number!
May 23rd, 2014 ADDENDUM:
Before the important informational contributions of Mr.
Edward Snowden, it was generally believed the above to be
essentially factual. Today however, it
is possible that even TLS/SSL encryption does not guarantee
integrity of messages, unfortunately. In all respects, the
author of the above answer is, we believe, correct.
Unfortunately, there are other ways to intercept and read
date in transit via mechanisms such as the MitM (Man in the Middle)
attack, even without the involvement of the NSA.