Both TNT Basic and the Hieroglyph IDE are open source. You can download the source code from http://sourceforge.net/projects/tntbasic.
We are always looking for people to contribute to TNT Basic's development, whether through programming, documentation, examples or graphics - all help is welcome. Take a look at the website above, or look at the community forums at http://www.tntbasic.com/community/forums/ to see how you could help.
TNT Basic has been released under a triple license consisting of:
What this essentially means is that you can choose which of these three licences you want to use the source code under. This places the fewest restrictions on the source code use in other projects, whilst still ensuring that improvements made to the source code make it back into TNT Basic, as is only fair.
The Mozilla license (MPL) is a fairly flexible open source license, if you choose to use the TNT Basic source code under MPL, then you can use it in your proprietary projects, with the only requirement being that you must release any modifications you make to the TNT Basic source code you are using back into the open source community. Using TNT Basic source code under the MPL DOES NOT require you to release the rest of your project's source code. This is in direct contrast to the more 'viral' GNU GPL license, described briefly below. For more information on the MPL, please refer to http://www.mozilla.org/MPL/. The annotated MPL and the MPL FAQ pages are particularly helpful to the non lawyers amongst us!
If you choose to use the TNT Basic source code under the GNU GPL, then the rest of your project's source code must also be released under GPL. This is due to the GPL requirement that any project that makes use of any GPL covered source code must have its source code released in its entirety. Making the TNT Basic source code available under the GPL has been done to allow existing GPL covered projects to use TNT Basic source code. Had the TNT Basic source code not been made available under GPL, then existing GPL projects, which require all source code to be under GPL, would not be allowed to use it.
For similar reasons, you can also choose to use the TNT Basic source code under the GNU Library or Lesser Public License (aka the LGPL). This license means you can compile the source code into a library, and in doing so all the source code within that same library has to be released under the LGPL, but the rest of the project which links to the library does not have to have its source code released. Again, this has been included as an option to allow existing LGPL projects to use the source code.
You can find more information about the GNU GPL and the GNU LGPL at http://www.gnu.org/licenses/licenses.html.