Java Tutorial - Java Script :
When comparing commercial software, one of the features that would normally be represented is purchase price. Most open source software is free. Instead of price, what becomes important is the open source license used to distribute the software. As discussed in Chapter 1, different licenses have different limitations on how the product can be used. Let’s say, for example, that you are evaluating database products for inclusion as an embedded part of
your application, and you want to be able to distribute your application commercially without revealing the source code to your customers. In this case, you might want to avoid using products with the GNU Public License (GPL)
because the GPL requires derivative works to also be published under GPL. This was among the reasons that Apple chose FreeBSD over Linux for the base of Mac OS X; FreeBSD is under a less-restrictive license (the FreeBSD license) that does not require derivative works to be published, as the GPL does. As you can see, it is important to understand the various open source licenses and treat the license as a feature or attribute of the software component.
