The Baroque guitar is a guitar

Guitar

The guitar is a plucked string instrument, usually played with fingers or a pick. The guitar consists of a body with a rigid neck to which the strings, generally six in number, are attached. Guitars are traditionally constructed of various woods and strung with animal gut or, more recently, with...

 from the baroque era

Baroque music

Baroque music describes a style of Western Classical music approximately extending from 1600 to 1760. This era follows the Renaissance and was followed in turn by the Classical era...

 (c. 1600–1750), an ancestor of the modern classical guitar

Classical guitar

The classical guitar is a 6-stringed plucked string instrument from the family of instruments called chordophones...

. The term is also used for modern instruments made in the same style.

The instrument was smaller than a modern guitar, of lighter construction, and had gut strings. The frets were also usually made of gut, and tied around the neck. A typical instrument had five course

Course (music)

A course is a pair or more of adjacent strings tuned to unison or an octave and usually played together as if a single string. It may also refer to a single string normally played on its own on an instrument with other multi-string courses, for example the bass string on a nine string baroque...

s, each consisting of two separate strings although the first (highest sounding) course was often a single string, giving it a total of nine or ten strings.

The conversion of all courses to single strings and the addition of a bass E-string occurred during the era of the early romantic guitar.
Three different ways of tuning the guitar are well documented in seventeenth century sources as set out in the following table.