Uniform Resource Locators (URLs) or other network information identifiers are transmitted with television signals in order to permit web content to be displayed in synchronization with television programming. In an illustrative embodiment, URLs are embedded in a closed caption portion of a transmitted television signal, and delimited from the closed caption text using predetermined delimiting characters. A decoder extracts the URLs from the television signal, and supplies the URLs to a retrieval device which automatically retrieves corresponding web pages or other similar information over a network. The retrieved web pages are then displayed to a viewer in synchronization with related programming in the television signal. The retrieval device may be a set-top box associated with a television set that displays both a retrieved web page and the corresponding television picture portion of the television signal. Alternatively, the retrieval device may be a computer which retrieves and displays a web page, while the corresponding television picture is displayed on a television set.