Teach yourself JavaScript

https://www.geeksforgeeks.org/javascript-tutorial/

Developing custom sections in JavaScript

https://www.lianja.com/doc/index.php..._in_JavaScript

Developing custom gadgets in JavaScript

https://www.lianja.com/doc/index.php..._in_JavaScript

Understanding UI layouts

https://www.lianja.com/doc/index.php...ing_UI_Layouts

Understanding Custom delegates

https://www.lianja.com/doc/index.php...stom_Delegates