The inventor of the World Wide Web says the internet as we know it is "under threat" and faces "heaps" of problems.

Monday 12 March marks 29 years since Sir Tim Berners-Lee created the World Wide Web. This year is expected to be the first time that more than half of the world’s population will have internet access.

Sir Tim spoke to the BBC's technology correspondent Rory Cellan-Jones about the challenges faced.