A colleague asked me about open source yesterday. As I tried to explain it to him, I realized that the phrase "open source" has a lot of meanings wrapped up in it. Here's an attempt to tease out a few of those.
Open source refers to the license. When you buy software, you're buying a license to use that software. With open source, there is no charge to license the software. But, the software is still subject to the licensing terms; it is not in the public domain. There are dozens of open source licenses. The most widely known and used of these is the GNU General Public License. Unlike most other commercial licenses, its actually readable, and well worth the read.
Open source also refers to a software development model. Eric Raymond laid this model out in his famous essay, "The Cathedral and the Bazaar" (also a book). In open source development, many programmers work cooperatively on the code. Most aren't working for profit, but because they enjoy it or they want to improve a particular piece of code. Some companies, like IBM and RedHat, have their employees work on open source software as a part of their jobs. Regardless, the point is that software can be developed, as some argue, faster and better under the open source model. Raymond develops this idea further, so I'll leave it to him.
Open source software is widely used. It might be free, but a lot of it is quite good, too. Linux is a great server OS, and its been making inroads as a workstation OS. Apache is the most widely used webserver software. Mozilla is a great web browser, and it forms the core of all recent Netscape releases. Speaking of browsers, KHTML is an open-source HTML library used by Apple in their new Safari web browser. OpenOffice is a MS Office replacement. MySQL and PostgreSQL are great open source relational database products. PHP, Perl, and Python are great open source programming languages. The Gimp, despite its odd name, is an open source image editor (like photoshop). And there are tons more. Thousands. (Granted, lots of those thousands aren't going be very good, but there is still tons of good stuff.)
A few more thoughts on the subject:
Open Source Initiative's Open Source Definition.
Differences between the "Free Software" movement and the "Open Source" movement.
Posted by Karl
March 12, 2003 09:36 AM