The contestants are required to do housework and are assigned tasks by the producers of the show (who communicate with the housemates via the omnipresent authority figure known to them only as "Big Brother").

The format has become an international TV franchise.

While each country or region has its own variation, the common theme is that the contestants are confined to the house and have their every action recorded by cameras and microphones, and that no contact with the outside world is permitted.

The results range from violent or angry confrontations to genuine and tender connections (often including romantic interludes). Although the show typically broadcasts daily updates during the evening (sometimes criticized by viewers and former contestants for heavy editing by producers), viewers can also watch a continuous feed from multiple cameras on the Web in most countries.

These websites were successful, even after some national series began charging for access to the video stream.

Housemates are voted out (usually on a weekly basis) until only one remains and wins the cash prize.

During their stay in the house, contestants are continuously monitored by live television cameras as well as personal audio microphones.This added a survivalist element to the show, increasing the potential for social tension.Nearly all later series provide a modern house for the contest with a jacuzzi, sauna, VIP suite, loft and other luxuries.In the first season of Big Brother, the house was very basic.Although essential amenities such as running water, furniture and a limited ration of food were provided, luxury items were often forbidden.However, the UK version introduced a larger number of contestants with weekly evictions.