DDC stands for Digital Compact Cassette. DCC was a sound recording format developed by Philips and Matsushita. It debuted in 1992 with the same form factor as analog cassettes. DDC was pitched as the successor to the analog cassette and competition for both DAT and MiniDisc. DCC players/recorders were backwards compatible with analog cassettes (that is they would play both the digital, cassettes and the older analog cassettes). Supporters of the format at the time touted the move to digital audio without the need to throw away analog cassettes.
PASC (Precision Adaptive Sub-band Coding) , an audio compression codec was used with DCC, and allowed it to store about 105 minutes per cassette; compare that to 180 minutes with DAT. DAT used uncompressed PCM so DCC was never considered to be better than it. However, many agreed that DCC provided better quality than ATRAC.
DCC had a short life in the market. It was discontinued by Philips in 1996 due to poor sales.