Port Number
Port Numbers may be physical or logical. The most common use of the term port is in IP based application protocols, and is used to describe the SAP (Service Access Point) through which the transport protocols, such as TCP (Transport Control Protocol) or UDP (User Datagram Protocol), pass information to the higher layers, and vice versa. The port numbers that are associated with the higher layer application protocol are assigned through the IANA and are classified as follows: Well Known - 0 to 1023, Registered - 1024 to 49151, Dynamic - 49152 to 65535.
