Protocol/service name The port number Introduction to the
ftp 20 and 21 File Transfer Protocol Indicates the File Transfer Protocol, 20 for connection and 21 for transmission
ssh 22 Secure Shell A protocol that provides security for remote login sessions and other network services
telnet 23 Unsafe text transfer
smtp 25 Simple Mail Transfer Protocol Simple Mail Transfer Protocol
DNS 53 Domain Name System Domain Name resolution
DHCP 67/68 Dynamic IP protocol
http 80 Hyper Text Transfer Protocol Hyper Text Transfer Protocol for Web browsing
https 443 Hypertext Transfer Protocol Secure Is used for Secure Web browsing
The Shared file 445 The ability to secretly share your hard drive through this port, and even format it without anyone noticing
pop3 110 Post Office Protocol
Remote Desktop Port 3389 Can connect to your computer remotely and do bad things
WWW proxy service 8080 Apache Tomcat Web Server for Web browsing