No, fortunately not. Joomla 2.5 and 3.x are built to support multiple languages out of the box and there is no need for 3rd party extensions, unless there are very specific or peculiar needs for your site. For most users, default built-in multi language capabilities of newer Joomla versions will be enough.
In order to use multiple languages you must install the desired language packs, activate languages and then follow the strict yet not-too-complicated procedure for building a multilanguage website in Joomla.
If you have additional questions regarding multiple languages and your Joomla-based website, please contact us.