How many strings does a guitar usually have?

Explanation

The guitar is a plucked string instrument, usually played with fingers or a pick. The term refers to a number of different types of instruments from the classical Spanish guitar to electric guitars. Guitars usually have six strings tuned in quarter notes with a third in the middle (E-A-d-g-h-e). The strings can be made of nylon or metal. The history of the guitar stretches back to at least 2000 B.C.