The "father of the personal computer" who kick-started the careers of Microsoft founders Bill Gates and Paul Allen has died at the age of 68.

Dr Henry Edward Roberts was the inventor of the Altair 8800, a machine that sparked the home computer era.

Gates and Allen contacted Dr Roberts after seeing the machine on the front cover of a magazine and offered to write software for it.

The program was known as Altair-Basic, the foundation of Microsoft's business.

"Ed was willing to take a chance on us - two young guys interested in computers long before they were commonplace - and we have always been grateful to him," the Microsoft founders said in a statement.

"The day our first untested software worked on his Altair was the start of a lot of great things."

Apple co-founder Steve Wozniak told technology website CNET that Dr Roberts had taken " a critically important step that led to everything we have today".

Full story: BBC News