American scientist Larry Roberts who helped design and build the forerunner of the internet has died aged 81.
In the late 1960s, he ran the part of the US Advanced Research Projects Agency (Arpa) given the job of creating a computer network called Arpanet.
He also recruited engineers to build and test the hardware and software required to get the system running.
Arpanet pioneered technologies underpinning the internet that are still used today.
Dr Roberts is recognised as one of the four founding fathers of the internet along with Bob Kahn, Vint Cerf and Len Kleinrock.