BASIC INFORMATION:
Internationalization i18n is the process of designing a software application so that it can be adapted to various languages and regions without engineering changes. Localization l10n is the process of adapting internationalized software for a specific region or language by translating text and adding locale-specific components. [1]
This framework comes with buildin English to Finnish translations:
Warning:
The locale information is almost always maintained per process, not per thread. If PHP runs on a multithreaded server API, there might be sudden changes in locale settings while a script is running, though the script itself never called setlocale(). This happens due to other scripts calling setlocale() in different threads of the same process at the same time. [2]
On Windows, locale information is maintained per thread as of PHP 7.0.5.[3]
The Translator is the base interface for human language translation related operations. It supports both basic and plural Gettext style translation.
A translator without any translations will do nothing but return all messages verbatim.
A Translator implementation supports both basic and plural Gettext style translation. It has also a method similar to PHP's native vsprintf() function for both basic and plural translations. Additionally the class contain a method for translating a multidimensional array containing singular translatable message strings (plural form is not supported).
A Gettext object translates given input by using PHP's build in gettext extension.