Sky Go (formerly known as Sky Player, Sky Anytime on PC and Sky By Broadband) is an online television service from Sky which launched in January 2006. The service allows users to watch live and on demand video content from their Mac, Windows PC, mobile phone or Xbox 360 via a broadband or Wi-Fi internet connection. On demand content comprises sports highlights, latest news, movies and TV programmes. Content is viewable for a limited amount of time and is protected by digital rights management software provided by Microsoft and the NDS Group, and therefore cannot be copied to disc or viewed beyond the date carried by its license. The service is available at no extra cost to existing Sky TV customers, with accessible content depending on the subscriber's Sky package. Non-Sky TV customers can access the service by subscribing on a pay-per-view basis.

Sky Go is viewable on up to two devices. The Microsoft Silverlight 3.0 browser plug-in is required to play content on computers. Due to viewing rights, certain programmes are not available to watch via Sky Go, and are 'blacked out' from the schedule. In order to have access to the full selection of live TV channels available on Sky Go, users will need either a Sky Multiroom or Sky Broadband Unlimited subscription, on top of the required TV packages that correspond to the available channels.

The sky, also known as the celestial dome, commonly refers to everything that lies a certain distance above the surface of Earth, including the atmosphere and the rest of outer space. In the field of astronomy, the sky is also called the celestial sphere. This is an imaginary dome where the sun, stars, planets, and the moon are seen to be traveling. The celestial sphere is divided into regions called constellations. Usually, the term sky is used from the point of view of the Earth's surface. However, the exact meaning of the term can vary; in some cases, the sky is defined as only the denser portions of the atmosphere, for example.

During daylight, the sky appears to be blue because air scatters blue sunlight more than it scatters red. At night, the sky appears to be a mostly dark surface or region scattered with stars. During the day, the Sun can be seen in the sky, unless obscured by clouds. In the night sky (and to some extent during the day) the moon, planets and stars are visible in the sky. Some of the natural phenomena seen in the sky are clouds, rainbows, and aurorae. Lightning and precipitation can also be seen in the sky during storms. Birds, insects, aircraft, and kites are often considered to fly in the sky. As a result of human activities, smog during the day and light pollution during the night are often seen above large cities.