Musical instruments are of many kinds, the main categories being chordophones (strings), aerophones (woodwinds and brasses), idiophones (percussion), and membranophones (drums).

Chordophones are those that are played by plucking or strumming at the strings. The sound produced depends on the mass of the string, length of the vibrating portion of the string, and its tension as well as the kind of resonating cavity in the instrument.

Aerophones generate music when air enters and vibrates within the instrument. This is possible by blowing into the instrument. The kind of music produced depends on the length of the column of air, the shape of the instrument, the method of tone production and the construction of the instrument.

Idiophones instruments, on the other hand, are those that produce sounds when struck. The sound generated is based upon the shape of the resonating cavity, as well as the size of the instrument. Other kinds of musical instruments are the pianos, keyboards and electronic instruments. Each of these musical instruments has sub-categories within them.

Dealers of musical instruments are generally middlemen between the manufacturers and the customers. They can be wholesalers, retailers, associations, even manufacturers themselves. Musical instruments dealers also sell other accessories like guitar amps, keyboard controllers, computer music hardware, stands and footstools, cables and cable accessories, speakers, straps and strap locks, microphone accessories, studio furniture, racks and cases, acoustic foam, headphones and headphone amps, covers, power supplies and batteries, music books, and more.

These days, musical instrument dealers have their own websites where they display their products along with the prices and any special offers or deals. Products can be ordered online or through fax, e-mail, or mail-order forms. Some also provide appraisal, repair, and restoring services. Some dealers specialize in old and antique musical instruments or secondhand instruments. Musical instruments can also be categorized on the basis of their playing levels. Some are suitable for all kinds of players while others are for novices. Expert players have very specific preferences where musical instruments are concerned. A dealer has to understand the needs of the player and suggest the perfect instrument accordingly.