Machine tool accessories is a need for users to be able to quickly and easily install or remove particular cutting bits or other accessories from the powered rotating spindle of the machine tool. Lathe headstock has a rotating spindle to which one may want to mount a spur drive. The machine tool can present a threaded spindle, to which accessories are screwed. The machine tool may have a permanent chuck. The different types are collet chuck, jaw chuck, lathe chuck, Sjogren speed chucks, and 5c collet chuck.

A simple, low cost, and versatile option is to hollow out a truncated conical void in the rotating spindle, coaxial with the axis of rotation. Tools or accessories can then have a mating male conical shaped shank, which precisely fits into the void. The pressure of the spindle against the workpiece serves to drive the tapered shank tightly into the tapered receptable. The friction across the entire surface area of the interface provides a surprisingly large amount of torque transmission; so that splines or keys are not required. This system is known as a machine taper.

House music is a style of electronic dance music, the earliest forms of which originated in the United States in the early- to mid-1980s. The name is said to derive from the Warehouse nightclub in Chicago, where the resident DJ, Frankie Knuckles, mixed classic disco and European synthpop recordings. Club regulars referred to his selection of music as house music. However, since Frankie was not creating new music at that time, it has been argued that Chip E. in his early recording "It's House" defined this new form of electronic music and gave it the name house music. However, Chip E himself claims the name came from methods of labelling records at the Importes Etc record store he worked at in the early eighties. People would come in looking for music Knuckles played at the Warehouse, so eventually a sign was put up that said "As Heard At The Warehouse". Eventually it was shortened to simply "The House", and the name became the vernacular.

The common element of house music is a prominent 4/4 beat (a prominent kick drum on every beat, also known as four-on-the-floor) generated by a drum machine or other electronic means (such as a sampler), together with a continuous, repeating (usually also electronically generated) bassline. Typically added to this foundation are electronically generated sounds and samples of music such as jazz, blues and synth pop, as well as additional percussion. As new recordings adhering to this general style emerged, the house genre divided into a number of subcategories

House Music also refers to the recorded music played while a theater audience takes their seats before a performance, or, in live music venues, the recorded music played before the live music begins. Well-known live acts can demand their choice of house music, or that there be none at all. Such demands are made in the technical rider to their contract