When more than one application is running on a server how does IP know which service should be presented an incoming data packet?

When multiple applications are running on a server, the operating system uses ports to distinguish between them. Each application listens on a specific port number, which is part of the transport layer protocol (like TCP or UDP). When an incoming data packet arrives, the server checks the destination port number in the packet's header and forwards the packet to the corresponding application based on that port. This way, the server can effectively route incoming data to the correct service.