Without getting into the technical aspects of what that is, the result is that it would take a hacker, using the most powerful of supercomputers, about 8 years to unscramble an intercepted message encrypted like this. In fact, this is the primary method used for acquiring credit card numbers and using them in credit fraud. Simply put, it is 10,000 times more likely for this type of fraud to happen to you face to face at your local retailer or restaurant, than on the internet. There are two ways, and both should be found on the site to be sure it is using encryption. First, look for a logo of a reputable security provider.
Different browsers handle or signify security in different ways.
If you are concerned about security, then make a point to become familiar with your browser's security features. Usually, there is some documentation in the help menus in the browser. So if these two conditions have been met on the web site you are visiting, you can feel secure that only the folks who are supposed to get your personal information will be the only parties to receive it. Another thing to remember on the web are some issues that may seem like common sense. But you would be suprised how many people fail to consider these simple guidelines.