That means you
get the source code and also the right to modify and redistribute it,
provided you do so under the terms of the GPL. That is, your
application must also be Free Software and you must provide source
code for it.
We like Free Software, but be warned that you
aren't allowed to publish it through certain distribution
channels. For example, you can't legally distribute code under this
licence on the iOS or OS/X App Stores, or in the form of VST
plugins. Both of these are controlled by companies that impose
restrictions on what sort of software they allow.
Using MiniBPM in proprietary commercial applications
For commercial software development, we provide a very simple
and flexible licence which allows you to take the MiniBPM
code, modify it if desired, and redistribute it in proprietary
products. No expiry date, no royalties.