Vocaloid (ボーカロイド Bōkaroido) is a singing voice synthesizer. Its signal processing part was developed through a joint research project led by Kenmochi Hideki at the Pompeu Fabra University in Spain in 2000 and originally was not intended to be a full commercial project. Backed by theYamaha Corporation, it developed the software into the commercial product "Vocaloid." 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. To create a song, the user must input the melody and lyrics.
A piano roll type interface is used to input the melody and the lyrics can be entered on each note. The software can change the stress of the pronunciations, add effects such as vibrato, or change the dynamics and tone of the voice. Each Vocaloid is sold as "a singer in a box" designed to act as a replacement for an actual singer. The software was originally only available in English starting with the first Vocaloids Leon and Lola, and Japanese with Meiko, but Vocaloid 3 has added support for Spanish for the new Spanish Vocaloids Bruno and Clara, Chinese for Luo Tianyi and Korean for SeeU.