Three radio standards, three very different trade-offs. Here’s the short version.
AM travels furthest, especially at night, and is still the backbone of emergency broadcasting because it keeps working when other infrastructure doesn’t. Sound quality is the lowest of the three.
FM sounds noticeably better than AM and covers most local stations, but range is limited to roughly line-of-sight from the transmitter.
DAB+ is digital, so stations are labelled by name instead of frequency, sound quality is consistently higher, and one signal can carry several stations at once. Coverage depends entirely on whether your country/region has built out DAB+ transmitters.
If you want one radio that covers all your bases, look for a tri-band set — most of our portable radios support all three.