* Musical instruments are devices designed to produce music, frequently by plucking or striking a string or bell or drum surface, or by forcing air to resonate (see wind instrument).
* Scientific instruments are devices intended to assist in the conduct of science. An example would be the test tubes and other glassware one might find in a chemistry or biology laboratory. Scientific instruments are not limited to laboratory equipment; an example is the Hubble telescope. Specific categories of scientific instruments include
o Measuring instruments are devices used to measure or compare the magnitude of physical properties, such as voltmeters, speedometers, timers and clocks, weighing machines,etc.
o Analytical instruments are devices used to measure multiple or complex material properties, such as mass spectrometers.
o Astronomical instruments are use to observe, record and measure the position of heavenly bodies, such as stars, planets, comets etc.
* Flight instruments are devices used to maintain attitude of aircraft in IMC.
* Medical instruments are devices for the diagnosis and treatment of diseases, such as stethoscopes.
* Instruments of torture is a term for the means whereby some act of torture is accomplished.
* Legal instruments are documents used to formally document various types of transactions or confirm certain statuses for specific purposes, such as confirming contractual relations, civil status, etc. Examples include wills, writs, court order, contracts, treaties, marriage licenses and driver's licenses.
* Financial instruments are documents used to formally document various types of financial transactions. Examples include loan agreements, bonds, mortgages, stocks and floating charges.
* Negotiable instruments are a class of documents evidencing promises or orders to pay a certain sum of money.
* In statistics, an instrument is an instrumental variable.
* A statutory instrument refers to a regulation or other secondary legislation passed pursuant to authority given by primary legislation.
* Vehicle instrument (i.e. speedometer, fuel gauge...), analogical or, nowadays, digital.
* Instrument - a documentary film about the band Fugazi.
* INSTRUMENTS is a band from Halifax, Nova Scotia, Canada.
* Instruments is a performance visualizer built in to Mac OS X v10.5.
* Instruments - An Instrumental/Math/Emo/Post rock Band in London
