To authenticate an Internet web site, the web site is verified each time it is accessed by a user browser. On receipt of a page request, the web site generates a web page into which is embedded a unique identifier. A Java applet for execution of the verification process may also be embedded or may be resident on the user browser. At the user, the browser instantiates the applet and extracts the unique identifier which is sent, together with browser and web site location data to a verification server. The server performs a lookup comparing the unique identifier and its address with a record of the correct identifier and address. Based on the comparison, an approval status is generated and sent back to the browser. This is displayed as a graphic in the browser. The graphic includes an animated portion to increase security.