What are some alternatives?
When comparing FL Studio and Reaper, you can also consider the following products
LMMS - Make music with a free, cross-platform tool
Audacity - Audacity is a free and open-source audio production software suite that includes a surprising array of editing tools and recording systems.
Ardour - Record, edit, and mix on Linux, Mac OS X, and Windows.
GarageBand - GarageBand is a fully equipped music creation studio for Mac
Ableton Live - Ableton makes Push and Live, hardware and software for music production, creation and performance. Ableton´s products are made to inspire creative music-making.
Reason - Reason is a program that you can use to create music.