Many web pages and applications are now highly integrated with external services around the web. For example, websites often embed functions like maps and videos. Each website does not create these functions independently - they use an application programming interface (API).

APIs make it easier for groups and organisations to share content online. Sites such as Royal Mail, Twitter, YouTube, Facebook and the BBC use APIs to make it easier for other websites to interact with their services. Google, Bing and Open Street Map have created APIs for their maps to encourage other websites to use this service.

APIs are invisible to the user of the website, but are of interest to people creating web apps.

A mashup is a website or application which mixes code from different external sources. There are many pieces of code that could be embedded into a site to create a mashup, including photo galleries, social media feeds and RSS news feeds.

Using APIs

The BBC Playlister is a quick, simple way to find and keep track of music. BBC, Spotify, Deezer and YouTube have collaborated using an API so that users can use music playlists on these different services.

Playlister uses a Spotify API. Spotify’s intellectual property rights have been made available by the Spotify Service through its API. The track metadata in the application comes from Spotify.

As well as building up their own personal playlist of tracks, users can export and listen to them on their chosen music service.