What makes a Web site secure?

A secure Web site uses encryption and authentication standards to protect the confidentiality of information sent during Web transactions.  Encryption is a way of scrambling data so that only the computer and the Web server involved in the transaction can decipher the personal or confidential information.  The most common protocol used for encrypting data is Secure Socket Layer (SSL).  When you connect to a Web site using SSL, your Web browser confirms the identify of the server, or authenticates it, using a digital certificate.  Most Web browsers are configured by default to use SSL for secure sites and to warn you when you enter or leave a site using SSL.

How do I know if the Web site I am browsing is secure?

In addition to the warning messages that many browsers use when you enter or leave secure sites, most browsers also display a security icon, usually a small locked padlock, when you are on a secure Web site.  For Internet Explorer, the icon appears in the lower right corner of the browser.  Mozilla Firefox also displays a padlock icon in the bottom right corner of the browser, in addition to changing the Web address field to yellow and displaying the padlock icon at the end of the Web address field.  For Safari, the icon appears in the upper right corner of the browser.

Secure site icon in Mozilla Firefox

You should also check the URL (Web site address) to see if the site is secure.  Secure Web sites will start with https:// instead of just http://.  For general Web browsing, URLs beginning with http:// are fine, but when transmitting payment information or other secret data, you want to be sure the site begins with https://.