Logic was a popular sequencer program made by Emagic. In 2002 it was acquired by Apple and the Windows version of Logic was discontinued. While early versions of Pro Tools concentrated on audio recording using digital signal processing (DSP) cards, the strength of Logic was its musical instrument digital interface (MIDI) capability. As computer processing power increased so did the ability to record audio without the need for extra DSP power. Logic was therefore able to add audio recording capabilities. Pro Tools also developed its MIDI technologies, so Logic and Pro Tools gradually overlapped in their feature sets, both becoming full MIDI sequencer and digital audio workstation packages.
Logic comes in two different versions, Logic Studio and Logic Express. Logic Studio incorporates the Logic Pro package and a number of effects and utilities, such as Apple Loops, MainStage and WaveBurner. Logic Pro also enables Logic to be used as a front-end sequencer, giving users the ability to work with all the Logic recording, editing and arranging windows while accessing Pro Tools hardware such as the 003 or Pro Tools HD systems. Logic Express is a cut-down version that allows the user to access the built-in audio capabilities of a Mac computer or a third party interface via a Core Audio driver.
Pro Tools comes in three versions: Pro Tools HD, Pro Tools LE and Pro Tools M-Powered. Pro Tools HD is a professional system combining Pro Tools software with additional DSP cards to provide increased processing power. Pro Tools LE uses the computer's own processing power but requires a compatible audio interface to run. Pro Tools M-Powered is similar to LE but is designed to run with compatible M-Audio audio interfaces. All Pro Tools versions allow the user to record audio and MIDI and manipulate the recorded information using editing and mixing windows.