For a long time, my adopted definition of money has been this:
Money is an IDEA, backed by confidence. Nothing more, nothing less.
You make money by doing any of the followings:

1. Trading time for money - getting a job, being self-employed
2. Manifesting and using creative ideas - inventing something as a solution to a problem, creating works of art, etc
3. Leveraging on resources and other people - owning a business, investing