Acoustic guitars come in two distinct types - the traditional classical or the steel strung acoustic. Both kinds differ in sound and construction.
Classical Guitars
Sometimes called a Spanish guitar, the classical's most characteristic physical feature is the use of nylon strings. Having to use right hand fingers to pluck the strings means more space between the strings over the sound hole which, in turn necessitates a fingerboard that is slightly wider than other guitars.
Classical guitarists hold the instrument by raising the left leg (with a footstool), placing the guitar on that leg and holding the instrument in place with the right arm. Alternatively the left foot can be placed on the floor and a small support placed between the leg and the guitar. Either of these positions support the classical in a way that gives the player greater mobility and access to the strings and the fingerboard. By using a combination of fingers and fingernails to pluck the strings, a classical guitarist is able to generate a wide variety of sounds.
The Acoustic Guitar
There are many different variations on the construction of and materials used in acoustic guitars. More expensive types feature solid wood tops (usually spruce or cedar), sides and backs (often rosewood, maple or mahogany). Lower priced guitars can combine solid tops and laminated backs and/or sides. Entry-level acoustic guitars are usually made entirely of laminated woods. Necks are generally made of mahogany and fretboards are usually hardwoods, such as rosewood or ebony. The various combinations of the different woods and their quality, along with design and construction elements (for example, how the top is braced) are among the factors affecting the sound of the instrument. Many players and builders feel that a well made acoustic guitar's tone improves over time.
Since a steel-string guitar must withstand higher string tension than nylon-strung instruments, heavier construction is required overall. Steel-string guitars use different bracing systems to their classical counterparts, typically using x-bracing or ladder bracing instead of the fan bracing that is commonly found on classical and flamenco guitars.
