An identification of one of multiple types of Web browsers that a Web page supports, as well as an identification of one of multiple versions of that one type of Web browser that the Web page supports, is obtained. The Web page is displayed using the identified version of the identified Web browser type. A request for an identification of the identified version of the identified Web browser type can also be received from a program, such as a Web page script. In response to the request, an identification of the identified version of the identified Web browser type is being used to display the Web page is returned, and instructions of the program are executed based at least in part on the identified version of the identified Web browser type.