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I bet that many of today's programmers have heard about Open Source, but don't want to use the principle in their programs. That's a shame, because it's a beautiful concept.

I've tried to make the information in this article as brief as possible, so don't look weird at the many lists in this article. This is mostly information put together from various sources, just for usefulness. And, this is my first article and English is not my native language, so don't be too hard on me. Any comments (good or bad) and suggestions are always welcome!

For those people who don't know what the Open Source concept is, here is a brief description.

The idea behind Open Source

The idea behind Open Source is that by giving the source of a program away, people can learn from it, improve it, extend it and fix bugs. The Open Source concept goes hand in hand with free software. Free like in freedom, not price.

For example: Linux. Yes, Linux is Open Source too. Linus Torvalds developed the base of this operating system, and gave away the source. Currently, multiple major companies are working on their own Open Source versions of Linux (SuSE, Red Hat, Debian and Mandrake are some examples), and even many more people are working on it too. Thanks to this, bugs are fixed very fast (advanced programmers even fix bugs while using Linux), and functionality is extended.

Your own protection

When you give away the sourcecode of your very own program, how can you be sure that people won't steal it and say that it is their own? By using a license. A license protects your rights, and can help you in a lawsuit against anyone who infringe these rights. There are many licenses that may be used for Open Source programs. You can find them here. The two most widely used licenses are the GNU General Public License (GPL) and the GNU Lesser General Public License (LGPL). Here a short explanation of why these licenses are important:

  • People may copy your code under the same license.
  • People may modify and distribute the (modified) source code.
  • People can't say that they wrote your code (it's copyrighted or 'copyleft').
  • Patents may not make the program proprietary, so patents must be licensed for everyone's free use.
  • People can't change the license applied to the source code.

The difference between the GNU General Public License (GPL) and the GNU Lesser General Public License (LGPL) is that the latter permits use of the source code in commercial programs, while the GPL does not.

Why applying the license to your company's program(s)?

If your boss agrees upon applying the GPL or LGPL to the company's program(s), then the company will have the following benefits:

  • Faster software development.

    Many people work on the same project.

  • Faster bug fixes.

    When a bug is found, there are many people available who can fix the bug in no-time!

  • More people will use the program.

    The program's sources are available, and people help develop the program. Through this, many more people will get to know about the program.

  • The wishes of the general community will be automatically integrated in the program.

    Because the general community develops the program, the program will be more likely to satisfy the general community.

  • Less development costs.

    People help developing, mostly for free.

  • Better beta testing.

    Many people use the program. People from beginners to experienced users.

Implementing the GNU (Lesser) General Public License

If you want to put your program and source code under the (L)GPL or any other license, then you'll have to put a short notice at the top of each source file. You will also have to include the license itself, and put a short notice in the documentation. You can use these steps for any license, but since the GPL is the most common used license, I'll discuss that here. Follow these steps:

Source code files

Add the following notice to the top of your source files, and change the information to suit your program:

Copyright (C) [year] [name of author]

This program is free software; you can redistribute it 
and/or modify it under the terms of the GNU General Public 
License as published by the Free Software Foundation; 
either version 2 of the License, or (at your option) any 
later version.
This program is distributed in the hope that it will be 
useful, but WITHOUT ANY WARRANTY; without even the implied 
PURPOSE. See the GNU General Public License for more 
You should have received a copy of the GNU General Public 
License along with this program; if not, write to the Free 
Software Foundation, Inc., 59 Temple Place, Suite 330, 
Boston, MA 02111-1307 USA

Also mention how you can be contacted by paper and electronic mail.

Splash screen/About box

On the program's splash screen, or if there is no splash screen used in the About box, put the following notice:

[program name] version [versionnr.], Copyright (C) [year] [author's name]
[program name] comes with ABSOLUTELY NO WARRANTY.

And mention how the user can let the program show the license (or provide a 'License' button on the About box).

You may also want to place the OSI-approved or Open Source logo on your splash screen/About box. You can find it here.

License file

You must add a file containing the full license you use to the files that accompany the source files and your program. Usually, this is a file named COPYING.

Copyright disclaimer

If you work for an employer or school, then you should let them sign a copyright disclaimer. The how and why of this disclaimer is explained at the end of the GPL.

Open Source programs

Here is a short and incomplete list of Open Source programs that might replace (expensive) programs.

  • Windows -> Linux.
  • InstallShield installers -> NSIS (Nullsoft Scriptable Install System).
  • Photoshop & Paint Shop Pro -> The Gimp.
  • Microsoft Office -> OpenOffice.
  • Filesharing -> E-mule and Shareaza.
  • .NET Framework -> Mono.
  • MSN Messenger & AIM & ICQ -> Gaim.

Thousands of Open Source programs can be found at the following sites (among others):


I write this update, now many months since I first wrote this article. Open Source has always been a point of discussion, and will always be. As it worked out, this article got the best votes and the worst votes, and the rating got stuck somewhere in the middle.

There was one goal I wanted to achieve by writing this article, and I met that goal: to make people think about Open Source. Why Open Source? Figure that out by yourself. This article became part of the discussion, and I hope that this discussion will be continued for a long, long time...

Links and resources

You can find any useful links here:

About Daniël Pelsmaeker

Daniël is a student at the Hanzehogeschool in Groningen, Holland, where he studies Architecture.
He knows too much about computers, and thanks to that, unfortunately, everyone keeps asking him for advice and cyberaid.

A long, long time ago, in a galaxy far away... erhm. No!
When he was little, he knew little about computers. He started learning about them by pulling the PC's plug from the socket, and his mother constantly lost all her work.
Then, Commodore 64 programming started at the age of six:
1: PRINT "Hello world!"
2: GOTO 1

From then, trough QBasic, Visual Basic 4, 5, 6 and now Visual Studio 2002 with C# and .NET.

That was his history, in short.

Click here to view Daniël Pelsmaeker's online profile.

posted on 2005-12-29 15:30 梦在天涯 阅读(643) 评论(0)  编辑 收藏 引用 所属分类: Open source

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