Blu-ray disc successor announced by Sony and Panasonic

Last updated at 12:11
A disc being read by a laser

A replacement for DVD and Blu-ray discs has been announced by technology giants Sony and Panasonic.

They plan to develop a new optical disc that can hold at least 300 gigabytes of data - six times as much as Blu-ray discs.

The discs could be used for ultra-high-definition 4K movies which are too big to fit on Blu-ray discs.

A bright future for discs?

Discs have become less popular as people are streaming more videos online - or downloading them illegally.

179 million disc-based videos were sold in the UK in 2012, according to the British Film Institute - that's 14% fewer than in 2011.

New discs that can store more data could make the format more popular again.

Bluray disc
Discs are much cheaper to buy than SD cards

"The cheapest way to store lots of this material long term is going to be on an optical disc rather than a solid state drive in your laptop or tablet, or on SD cards," said digital video expert Paul O'Donovan.

Discs also offer a cheaper way to send people big files which aren't always easy to send online.

"Imagine trying to send a 300 gigabyte file over the internet - it would take ages," said Paul.