The social graph is a term coined by scientists working in the social areas of graph theory to describe a sociogram which depicts all personal relations. It has been referred to as "the global mapping of everybody and how they're related". The term was popularized at the Facebook f8 conference on May 24, 2007, when it was used to explain that the Facebook Platform, which was introduced at the same time, would benefit from the social graph by taking advantage of the relationships between individuals, that Facebook provides, to offer a richer online experience. The definition has been expanded to refer to a social graph of all Internet users.

A graph is an abstract concept used in discrete mathematics; the social graph describes the relationships between individuals online, as opposed to the concept of a social network, which describes relationships in the real world. The two concepts are very similar, but some minor differences do exist. For example, the social graph is digital, and more importantly, it is defined explicitly by all connections involved. Since explaining the concept of the social graph, Mark Zuckerberg, founder of Facebook, has often touted Facebook's goal of offering the website's social graph to other websites so that a user's relationships can be made aware and put to use on websites outside of Facebook's control.

Ian Scott Anderson, MBE (born 10 August 1947) is a Scottish singer, songwriter and multi-instrumentalist, best known for his work as the leader and flautist of British rock band Jethro Tull.

Ian Anderson was born the youngest of three children. His father, James Anderson, ran the RSA Boiler Fluid Company in East Port, Dunfermline, Fife, Scotland. Anderson spent the first part of his childhood in Edinburgh, Scotland. He was influenced by his father's big band and jazz records and the emergence of rock music, though disenchanted with the "show biz" style of early American rock and roll stars like Elvis Presley.

His family moved to Blackpool, Lancashire in 1959, where he gained a traditional education at Blackpool Grammar School. In a recent interview, Anderson stated that he was asked to leave Grammar School for refusing to submit to corporal punishment (still permitted at that time) for some serious infraction. He went on to study fine art at Blackpool College of Art from 1964 to 1966.

While a teenager, Anderson took a job as a sales assistant at Lewis' department store in Blackpool, then as a vendor on a newsstand. He later said it was reading copies of Melody Maker and the New Musical Express during his lunch breaks that gave him the inspiration to play in a band.