Generally, guitars are classified based on the types of strings, shape and size and broadly can be classified as acoustic guitars and electric guitars.

Acoustic guitars use acoustic method i.e. natural sound with no amplification tools, to produce sound and are the traditional form of guitars. This form of guitar is most suitable to play for a small audience and for playing folk music, though any music can be played on it. Usually, acoustic guitars have a large and hollow body and the tone generated by guitars varies with the size. A large bodied guitar is expected to generate heavier tone as compared to the one with small body. As acoustic guitars do not have inbuilt amplifiers, usually microphones or pickups are used for amplification. Piezo, magnetic pickups are most commonly used.

Various forms of acoustic guitars are:

• Classical Guitars: These guitars have wider neck and strings made of nylon. Usually, such guitars are used to play classical, ballad or Flamenco forms of music.
• Steel Guitars: The method of playing these guitars makes them unique in the wide range of Guitars. These are played horizontally, placing them across knees or on the stands and are available in two forms i.e. lap steel and pedal steel.
• Bass Guitars: The long and thick strings of bass guitars are typically used to generate bass of the rhythm. Bass guitars are available with four and six strings, while four strings guitar is most widely used.
• Twelve String Guitars: Contrary to the standard form of guitars, which have six strings, twelve string guitars come with a twelve strings put up together. Each pair is tuned at the same note; however, one of the strings is tuned at a higher octave. These guitars are comparatively costlier and also difficult to play.
• Resonator Guitars: Also known as resophonic guitars, these guitars aim to enhance the sound of the traditional acoustic guitars. Metal based resonators are incorporated to amplify the sound and are mostly used in country music, bluegrass and blues style of music.

Electric guitars are the basis of rock music and with vast usage in jazz, blues and pop music, electric guitars, require amplifiers. They usually have long necks and solid-body with pickups and amplifiers. Pickups play a crucial role in generation of sound and produce metallic sound with a lengthy decay. Among the different types of guitars, electric guitars are used to produce extensive varieties of tones, which are usually achieved by variations in design. The thin strings, control knobs make usage of electric guitars very easy with limited force.

A few other varieties are mentioned below:

• Archtop Guitars: These hollow guitars with arched top can be an acoustic guitar or electric guitar. The electromagnetic pickups, unique timbre at the top, sound block at the middle with violin f-holes make them unique. These forms of guitars are predominantly used in jazz music.
• Double-neck Guitars: These unique guitars with two necks and a body offer a distinctive guitar playing experience. Player can switch between necks, which usually might have standard six strings coupled with a twelve string neck or six-string fret with a fretless version or six strings with a bass.
• Electro-acoustic Guitars: As explained, acoustic guitars have subtle timbre which does not produce high volume of sound and hence electro-acoustic guitars incorporate specially designed pickups to enhance the sound generated.
• Harp Guitars: These guitars with open strings which can accommodate individual plucking usually have at least one unfretted string positioned off the main fretboard. Most of harp guitars are in the form of acoustic and are available in hollow arms, double necks models.
• Russian Guitars: These extremely popular guitars in Russia come with seven strings in acoustic form. These form of guitars offer greater flexibility and can be played without a pick. It is also available in double neck.

Though different forms of guitars are available, you can learn and enjoy playing on the one that is most suitable to your style. Hence, pick the most appropriate one from the wide range of guitars.