is Zend Studio Plugin for eclipse (3.6.1 up) is free?

Sorry I can't understand well the license agreement. Here is the link I followed to install Zend Studio as a Plugin.

Zend Studio as a开发者_StackOverflow中文版 Plugin

I know that Zend Studio IDE is not free. So taht, I am wondering if the plugin is not a free plugin.

is it

free to use? free to create personal/commercial site? no license violation at all?

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Zend Studio is commercial software. You can install it as a plugin if you have an existing Eclipse-based IDE but you will still be asked for a license key. PDT, however, is the free version of Zend Studio which has some of the standard code editing features.