Without any form of integration between the host machine and the guest, we would simply have a bare bones virtual server running on top of our own operating system, which is not particularly useful. We need our own machine to be capable of integrating tightly with the guest (virtual machine).
Although the virtual machine is running on our own machine, because of virtualization, it acts and behaves like a completely different machine. Sometimes, this is what we want; however, there might be times we want to have the virtual machine behave almost as an extension of our own machine. One way to do this is through port forwarding, where we can tunnel a port from the virtual machine to a port on the host machine. If, for example, we have a web server running on our own machine, we obviously don't want to map the web server port from Vagrant onto the same port; otherwise, there would be a conflict. Instead, we can map it to another...