Each Web server are highly customizable using hook functions. Many hook functions can be called by µC/HTTPs module during the processing of each client's request. This hook function allow the application to act differently following the application context. As example it's possible to implement functionality such as dynamic content replacement, authentication, adding HTTP header to the HTTP response (i.e. cookie), redirect, generate run-time data page, etc.
The figure below shows a simplified state diagram of when hook functions are called.