NAT stands for Network Address Translation, and it’s responsible for translating the individual IP addresses that belong to various devices on a local network into just one IP address. The scope of that is to allow any device that has its own network address and is connected to a router to access the web using the IP address assigned to you by your ISP.
When it comes to NAT, port forwarding can intercept the traffic that’s heading to a NAT-obtained IP address, and redirect it to another IP address instead.