It All Started With Radio
It all started with the Broadcasting Receiving Licence in 1922 to protect national security. The idea was to create a register of people capable of monitoring naval movements and radiotelegraph messages. It was later extended to television reception to which the BBC was given exclusive rights.
With the arrival of the transistor radio, the government bowed to the impracticality of enforcing the radio part of its licence and thus the radio part of the licence was dropped. When colour television appeared, a supplementary fee was levied. This two tier licence fee still stands today; one licence for black and white reception, another for colour reception.
Over the years, as new technologies emerged, the licence gradually morphed and extended its reach far beyond its original purpose. When the video recorder came out a licence was required as it contained a television tuner. Additionally, a colour licence was required for a video recorder even if a black and white television was used for viewing. These days, of course, from tablets to set-top boxes, there is no black and white option, negating a cheap option for those on low income.