Port Number helps computers distinguish between different services running on the same IP address. When data reaches a server, the port tells the operating system which application should receive it. Ports range from 0 to 65535 and are commonly associated with services such as DNS, email, FTP, SSH, HTTP, and HTTPS. Knowing which ports are open or required is important for troubleshooting connectivity and securing your infrastructure. Explore the complete Port Number guide to understand port ranges, protocols, and popular examples.