Interactive television standards are standards for television broadcasting that relate to different modes of interaction and feedback mechanisms. This interaction system is what creates an extension to the general, traditional television experience. The first stage of interactive television occurred in the 1980s with the introduction of Teletext in analog television. This standard, which simply added bits of data to invisible scan lines, allowed limited interaction with television sets to visualize extra textual and numerical information, such as show schedules and weather data, but also optional subtitles. Today, the technology has developed to a point that allows for a more complex, bidirectional communication. The early private broadcasters, such as Canal+, were the pioneers in adopting this new form and have continued to develop it over the years. As a consequence of the increasing obsolescence of the analog format, the project known as Digital Terrestrial Television (DTT) was developed, which created public television in digital format, in competition with private broadcasters. Among its new features was interactive menus, which (as in private broadcasting) gave information to the user and allowed them to adapt the product for their own needs. Today, this is known as interactive television. This interaction is possible due to Set-top-Boxes (STBs), television decoders that are able to receive a digital signal, decode it, and display it through an analogue television set. This device allows analog users access to the same content as the digital television net. Running interactive programs is one of the STB's functions, among others. STBs are required to be dynamically programmed and updated, often done by an intermediary software that runs both the applications and the audiovisual signals simultaneously. This intermediary software is referred to as middleware. Some STB systems allow updates via USB flash drives. Private standards or private property Media Highway Defined by Canal Plus Technologies, the media highway represents the wide range of middleware solutions that allow the STB software to do the following: interpret and execute interactive applications, broadcast software and data from servers to interactive applications via satellite, cable, and/or terrestrial nets. Other functions also include having different profiles to better respond to the needs of the broadcaster. These interactive applications can be written in different programming languages as Java, MHEG-5 or HTML, and can support the middleware specifications DVB-MHP, OCAP, DAVIC or ATSC, and other specifications. Open TV Core Open TV Core is the most important product from Open TV,