DAB
DAB, Digital Audio Broadcasting, is the original digital radio standard from which the newer and more efficient DAB+ was developed.
DAB stands for Digital Audio Broadcasting. It is a way of sending radio as a digital signal over the air, with several programmes sharing one frequency block.
The name is often used loosely for everything digital. In Switzerland that can mislead, because the country broadcasts exclusively in DAB+, according to dabplus.ch, which has been the case since 2016. A radio that says only DAB on the box may not be what you need. Look for the label DAB+ on the device or in the manual.
The two terms sit side by side in shops and in the news. When a Swiss source says DAB for the current system, it means DAB+.