Question

Is it possible to use CodeIgniter framework in commercial project and distribute it ?

Answer 1

From the CodeIgniter License Page: (emphasis mine)

Permitted Use

You are permitted to use, copy, modify, and distribute the Software and its documentation, with or without modification, for any purpose, provided that the following conditions are met:

1. A copy of this license agreement must be included with the distribution.
2. Redistributions of source code must retain the above copyright notice in all source code files.
3. Redistributions in binary form must reproduce the above copyright notice in the documentation and/or other materials provided with the distribution.
4. Any files that have been modified must carry notices stating the nature of the change and the names of those who changed them.
5. Products derived from the Software must include an acknowledgment that they are derived from CodeIgniter in their documentation and/or other materials provided with the distribution.
6. Products derived from the Software may not be called "CodeIgniter", nor may "CodeIgniter" appear in their name, without prior written permission from EllisLab, Inc.

(as of 2010-07-12)