Post by MarkKordusic

Your open source question: partly right.

• Linux is under the GPLv2, which is a "copyleft" license. If you modify it and distribute it, you must make your source available under the same license.
• You don't have to send changes to Linus or the main project. You only have to share them with whoever receives your version. If you keep your changes private and never distribute them, you don't have to share anything.
• Permissive licenses like MIT, BSD and Apache don't require sharing changes at all.
• Linus's strictness is mostly about the kernel development process. Patches have to meet high quality standards, and his famous rule is "we don't break userspace". That's separate from the license itself.