When one computer wishes to connect with another, it performs what is called a TCP handshake, or TCP socket. This is a three-way handshake that works a similar to introducing yourself to someone new on the street. Every time you make an Internet connection, this process happens at lightning speed in the background and you never even notice it. It works like this.
Let’s consider your computer to be the client and the server for the website you wish to visit the target. Your computer, the client, sends what is known as a SYN data packet over IP network (Internet). This packet will ask the external network of it is open for new connections. For the connection to be made, the larger server, such as the one at your Internet provider, must have an open port that can accept a new connection.
Once the larger server receives the SYN packet, it will send back the answer in the form of an ACK packet. Your computer receives the ACK packet and the connection is made. Once this connection is made, the Internet website will pop up on your screen and you can use it.