Which license should I use?

Kartik and Antonio Ramirez use BSD license for their extensions, while other Yii users use MIT or GPL.

I’ve noticed that many plugins available on the Internet are under GPL. For example http://www.phpfreechat.net or http://joomla.org are GPL.

I’m confused. Which license should I use for my yii extensions and non-yii extensions?

GPL and other copyleft licenses should only be used for applications where people are not going to use your code in their own applications.

For libraries/extensions/plugins/etc it is best to use BSD/MIT and other permissive licenses.

Of course, it depends on your philosophy what license you want to use.

Either you are idealistic and for copyleft (and maybe even a member of the FSF).

Or you are realistic and practical and for permissive licenses (because this is not the 70’ies). :P