How to include??

[KAR]

Hello all, im a c programmer for years, and recently and recently trying to switch for better language since my projects becoming biger and bigger, now i need faster language in terms of development but i never fan of c++, D looks promising but starting up can be frustating since not much in tutorial provided.

Can somebody tell me of source code filing structure, since ive been use #include and stuff for long, and not familiar with d module and import...