Violin typically are lower in pitch than the G-string; these strings are usually tuned to C, F, and B. If the instrument's playing length, or string length from nut to bridge, is equal to that of an ordinary full-scale violin; i.e., a bit less than , then it may be properly termed a violin. Some such instruments are somewhat longer and should be regarded as violas. Violins with five strings or more are typically used in jazz or folk music. Some custom-made instruments have extra strings which are not bowed, but which sound sympathetically, due to the vibrations of the bowed
Violin technique fingers on the right spots without such indications but from practice and experience. To attain good intonation, violin players train their fingers to land in the right places, learning to hear when a note is in or out of tune, and cultivating the ability to correct the pitch rapidly and automatically as notes are being played. "Singing" the note mentally helps to land in the right spot. (In practice, intonation may be checked by sounding an adjacent open string, and listening for the interval between the two notes.) Although adjusting to the desired pitch after landing the finger is indeed