Ableton software every version. I have every reputable music software out. If you don't see what you are looking for please ask.
Live is composed of two 'views' – the arrangement view and the session view. The session view is primarily used to organize and trigger sets of MIDI and audio called clips. These clips can be arranged into scenes which can then be triggered as a unit. For instance a drum, bass and guitar track might comprise a single scene. When moving on to the next scene, which may feature a synth bassline, the artist will trigger the scene, activating the clips for that scene. As of Live 6, "device racks" have been implemented which allow the user to easily group instruments and effects, as well as map their controls to a set of 'macro' controls.
The other view is the arrangement view, which is used for recording tracks from the session view and further manipulating their arrangement and effects. It is also used for manual MIDI sequencing, something for which a classical composer would have a greater affinity. This view is fairly similar to a traditional software sequencer interface.
Clips may either be an audio sample or MIDI sequence. MIDI triggers notes on Live's built in instruments, as well as third party VST instruments or external hardware.
By default, Live comes with two instruments - Impulse and Simpler.
Impulse is a traditional drum triggering instrument which allows the user to define a kit of up to eight drum sounds, each based on a single sample. There are a number of effects available such as basic equalization, attack, decay, pitch shift, etc. Once the kit is defined, rhythms and beats are created through Live's MIDI sequencer.
Simpler is a relatively easy-to-use sampling instrument. It works using a single sample, applying some simple effects, envelopes, and timing, and then applying pitch transformations in the form of Granular synthesis. In this case, incoming MIDI does not trigger drums as it does in Impulse, but selects the final pitch of the sample, with C3 playing the sample at its original pitch.
 Dedicated Hardware Instruments
Akai Professional makes the APC40, a MIDI controller designed to work solely with Ableton Live. A smaller version, the APC20, was released in 2010. Though there are hundreds of MIDI controllers compatible with Ableton, these Akai units try to closely map the actual Ableton Live layout onto physical space. Novation Digital Music Systems has created the "Launchpad" which is a pad device that has been designed for use with Ableton.
There are a number of additional instruments which may be purchased separately or as part of the Ableton Suite.
Amp - a device that delivers the sounds of various amplifiers and cabinet combos. It is the newest add-on and a part of Suite 8.2.
Sampler - an enhanced sampler.
Operator - an FM synthesizer.
Electric - an electric piano instrument.
Tension - a string physical modelling synthesizer.
Collision - a mallet percussion physical modelling synthesizer.
Analog - simulates an analog synthesizer.
Drum Machines - a collection of emulators for classic drum machines.
Session Drums - a collection of sampled drum kits.
Latin Percussion - a collection of sampled latin percussion hits and loops.
Essential Instruments Collection - a large collection of acoustic and electric instrument samples.
Orchestral Instrument Collection - a collection of four different orchestral libraries, which can be purchased individually or as a bundle: Orchestral Strings, Orchestral Brass, Orchestral Woodwinds and Orchestral Percussion. The Orchestral Instrument Collection is not included in Live Suite.