Sight-reading, also called a prima vista (Italian meaning "at first sight"), is the reading and performing of a piece of music or song in music notation that the performer has not seen before. Sight-singing is used to describe a singer who is sight-reading. Both activities require the musician to play or sing the notated rhythms and pitches. Many believe that sight-singing is the more challenging of the two, because singers do not have any keys, frets or valves (on keyboard instruments, guitars, and valved brass instruments, respectively) to help them obtain the correct pitches. Singers must also read and sing the correct lyrics, which adds another layer beyond pitch and dynamics. However, difficulty is related both to the instrument and the difficulty of the piece itself. For instance, sight-reading on a polyphonic instrument, such as the classical guitar, can be more challenging due to the fact that the guitarist has to read polyrhythms and polyphonic passages that can often be played in different positions using different frets.
People in music literature commonly use the term "sight-reading" generically for "the ability to read and produce both instrumental and vocal music at first sight […] the conversion of musical information from sight to sound". Udtaisuk and some other authors prefer the use of the more specific terms "sight-playing" and "sight-singing" where applicable. This differentiation leaves a third, more restricted use of the term "sight-reading" for the silent reading of music without creating sound by instrument or voice.
Highly skilled musicians can sight-read silently; that is, they can look at the printed music and hear it in their heads without playing or singing (see audiation). Less able sight-readers generally must at least hum or whistle in order to sight-read effectively. This distinction is analogous to ordinary prose reading during the early Middle Ages, when the ability to read silently was notable enough for St. Augustine to comment on it/ Franz Liszt was famous for his capacity to play advanced piano pieces sight-reading the notes.
The term a prima vista is also used, as Italian words and phrases are commonly used in music and music notation. To play a musical piece a prima vista means to play it 'at first sight'. According to Payne, "the ability to hear the notes on the page is clearly akin to music reading and should be considered a prerequisite for effective performance.... Egregious errors can occur when a student, analyzing a piece of music, makes no effort to play or hear the composition but mechanically processes the notes on the page".