This guide provides an introduction to the art of remixing music. It covers the basics of remixing, from understanding the fundamentals of music production to exploring the creative possibilities of remixing. It also provides tips and tricks for creating professional-sounding remixes
From Wikipedia
A remix, also sometimes called reorchestration or rework, is a piece of media which has been altered or contorted from its original state by adding, removing, or changing pieces of the item. A song, piece of artwork, book, poem, or photograph can be remixes. The only necessary characteristic of a remix is that it appropriates and changes other materials to create something new.