How is DAB digital radio different to analogue radio?

It's different because, instead of being made up of analogue waves, the radio signal is transmitted digitally, as a series of 'zeros and ones'. You don't need a satellite dish to receive digital radio, just an aerial positioned in the correct place. Traditional FM analogue radio waves are sensitive to noise or distortion from electrical equipment or from the atmosphere. The waves can bounce off tall buildings and hills and become interrupted or distorted.

As DAB digital radio uses digital signals, with plenty of extra information transmitted to allow the tuner to fill in any missing bits, the DAB signal does not suffer from the same problems as the FM signal. If you live in a weak signal area, you'll find that, even with all that extra information, the sound sometimes breaks up. If you live in a strong signal area, you'll find you have uninterrupted listening without 'drop-outs'.

Some history:

DAB digital radio was developed by a consortium of 12 partners, known as EUREKA-147 - the system was originally called Digital Audio Broadcasting (DAB) and this is still used to distinguish a true DAB receiver from all other radio receivers. In 1994, Eureka-147 was adopted as a world standard and, today, most of the world has either implemented the standard or is currently testing it. The exceptions are the United States, which has embraced both satellite digital radio and High Definition radio, and Japan where cable is the chosen method of delivery for new radio formats.