How can data come in my network if incoming ports are closed?

Question

On my home network router all incoming ports are closed. How is it possible for data to come in my home network? For instance, when I make an HTTP Request, which incoming ports are the HTTP response packets using to come in?

Answer 1

"Incoming ports closed" means that no connection attempts are accepted from the outside. If connections are initiated from the inside then a connection state is maintained and if incoming packets match this state they are allowed through.