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docs/plugin.md

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+# Plugins
+Here is a brief specification of the plugin module itself.
+All loadable plugin modules need to have an `init` method.
+
+## Backend
+Backend modules get two initialization parameters: `logger` and `LMathPluginAPI`.
+Feel free to use these in any way you want. Below you'll find a simple example.
+
+```js
+let logger, api;
+
+module.exports = {
+    init: (_logger, _api) => {
+
+        logger = _logger;
+        api = _api;
+
+        logger.info('Hewwo! It is me, the new plugin!');
+
+        api.messages.on('testMessage', (d) => {
+            logger.info('Someone sent me a message! ' + d);
+        });
+
+    }
+};
+```
+
+## Frontend
+Frontend modules also get two parameters: `window` (the actual window object) and `LMathPluginAPI` (frontend).
+jQuery and other useful things can be found like presented below.
+
+```js
+let window, api, $, jQuery;
+
+module.exports = {
+    init: (_window, _api) => {
+        
+        window = _window;
+        api = _api;
+        
+        $ = window.jQuery;
+        jQuery = window.jQuery;
+        
+        console.log('Hewwo wowld! This is the frontend side!');
+
+        setInterval(() => api.messages.send('testMessage', Date.now()), 2000);
+        
+    }
+}
+```