Editing allows you to fix problems in your tracks, make changes to the structure of a song and also create composite tracks.
Every digital recording system is different and I couldn't possibly cover all the variables that exist in the many different types of systems, but what I can do is show you the basic principles so that you understand what possibilities exist, thus applying these skills to the system that you own.
Changing The Structure Of A Song Easily
You can play just a portion of the song and assemble the song from there. For example, you can just record one verse and one chorus on each instrument.
Then by using your home recording software editor you can copy and paste the sections of the track to wherever you want them to be.
A composite track is a single track made up of the best bits of several different versions of tracks. So say for instance you record three takes of a guitar solo, each one had bits you liked but none sounded perfect on their own.
This is where making a composite track comes in. What you do is select, copy and paste the bits you like onto one track, blending them together to give a smooth natural sounding track. This is a great trick you can use when editing music to save a lot of time.