When a website visitor connects to a webserver using SSL they will see that the URL in the address bar begins with https:// rather than the usual http:// and also a small gold padlock will appear in their browser, e.g. 
As seen by users of Internet Explorer
Whenever a browser connects to a webserver (website) over https:// - this signifies that the communication will be encrypted and secure. The actual complexities of the SSL protocol remain invisible to the end customer.
In summary, SSL is the de facto web transaction security technology. Webservers have been built to support it and web browsers have been built to use it. SSL provides the ability to secure customers transactions transparently without the customer having to do a thing!
