AMD stands for Asynchronous Module Definition. In a nutshell, it’s a format or a specification for writing javascript.
So, what is a Javascript module?
Its a reusable code which exports specific objects, making them available for other modules through dependency references to be used their programs.
These modules can be loaded asynchronously, if desired. That means, there’s a huge improvement in website performance as the files are only loaded when they are needed. Also, it provides developers with the flexibility to define order in which module dependencies have to be loaded and load multiple javascript files during runtime.
AMD implementation is used by jQuery, Dojo, Firebug etc. There are various javascipt module loaders like RequireJS, Browserify, Webpack, SystemJS
Vivishine 