Might be my question is abstract or out of context, but i am asking here since i have little idea how this happens.

I am wondering how big application/ platform break down there application in to multiple module and how they able to manage modules dependencies.

For example in some E-commerce application they tend to break down it in various modules like pricing,promotions,shipping.import/export and many more. when we develop those application we hardly think about the underlying modules and how they have been designed to provides functionalists.

Most of those module are not web-applications but are standalone module and not deployed in the web-app as jar files.

can any one help me to understand how they break up things or is there any standard way to do this.any help/resources to get insight will really be helpful