Music and technology are inseparable. Advancement in the development of instruments and interfaces for musical expression is directly linked with the birth of new musical traditions. Emerging technologies have given musicians the ability to record, produce, and manipulate their work, from the comfort of their bedroom. Aside from being a tool for recording music, computers can be used as instruments. Unlike conventional instruments the computer can take many forms. Some instruments are fully reliant on a performer’s actions and will always work in a specific manner, while other instruments can actually perform without any input and can be multidimensional in their function and/or interaction. During this presentation various approaches of interactivity are explained, through a brief overview on the approach David Wessel, George Lewis, and David Rosenboom have taken while designing their interactive computer instruments.