![dek](https://content.time.com/time/photoessays/2010/100_gadgets/entertainment/sony_discman_d50.jpg)
The D-50 was the first portable CD player when it launched in 1984. More important, it stirred public interest in compact discs at a time when cassette tapes were still the norm. Small as it seems, the D-50 did not have its own power source, so it required a comically large battery-pack case that significantly increased its overall size. But some of the battery packs included shoulder straps in case you wanted to carry it around.