The basic answer.
Vocaloid is a singing synthesizer application. The software enables users to synthesize singing by typing in lyrics and melody. It uses synthesizing technology with specially recorded vocals of voice actors or singers.
- Additional information
Its signal processing part developed through a joint research project between the Pompeu Fabra University in Spain and Japan's Yamaha Corporation, who backed the development financially—and later developed the software into the commercial product "Vocaloid".