The tricky part of following the GPL and even the BSD license comes when you want to keep some of the code private. This isn’t as nefarious as it sounds. Many people write their own software, keep it secret, yet run it on top of Linux. Others write proprietary web applications and run them with a BSD-protected version of Apache running on top of a GPL-protected version of Linux. If you stay on the right side of the lines, you’re still Richard Stallman’s best friend. If you link the code together in the wrong way, though, you’re toast.
Link: slashdot.org
