License for CE

Hi everyone,

Recently i had downloaded Pentaho CE edition for a certain project of mine.
I'm also planning to move the same to production.

My concern here is that, do i have all the right or is it right from my part, to use CE for my business (to earn few dollars for service that i provide).
Is it a violation of any sort?

I know pentaho is open source, but is it free?.
Recently in a blog i found out, not all open source is free !!!.

I would be really grateful, if someone could help me on this.

Thanks in advance :),

JOE