2.the concept of TCP ports and their significance in establishing connections

TCP ports provide for multiple network applications on one machine by
means of network ports which are numbers used along with addresses.
Usign TCP, application opens a connection between one port on its own
machine and a port on a remote host. For e.g., an application such as a
web browser could open a connection between port 36406 on its own
machine and port 80 on a remote host.