# Port

A port is just a number that the host associates to an application. Ports break down into 3 groups

1. 0-1023 are well known ports,
2. 1024-49151 are user or registered ports, and
3. 49152-65535 are ephemeral ports.

Well known ports are used for system processes and protocols. For example port 80 is used by webservers for HTTP .

Registered ports are used for user applications that need a port to work off of.

The ephemeral ports or dynamic ports are used for private or temporary uses for example to connect to a web browser and receive a web page.