Most common service and Ports no.

Commonly!
The ports used to run various services (for example, web, email ) on the same IP. A Port can be any number from 0 to 65535.
The service name was assigned on a first-come,first-served process
and it is always in (three ranges)

System Port (0-1023)
User Port (1024-49151)
Dynamic/Private Port (4159-655235)

However, In with the growth of windows and single-user Linux systems; The ports model no longer works.
The most common service names and there ports no. are mentioned below:

Service Name Ports
FTP(File Transfer Protocol) 20,21
SSH(Secure Shell) 22
Telnet(Telephone Network) 23
SMTP(Simple Mail Transfer Protocol) 25
DNS(Domain Name System) 53
DHCP(Dynamic Host Configuration Protocol) 67,68
TFTP(Trivial File Transfer Protocol) 69
HTTP(Hyper-Text Transfer Protocol) 80
POP(Post OProtocol)ffice 110
NNTP(Network News Transfer Protocol) 119
NTP(Network Time Protocol) 123
LDAP(Lightweight Directory Access Protocol) 389
HTTPS(Hypertext Transfer Protocol Secure) 443
IMAPS(Internet Mail Acess Protocol Secure) 993
RADIUS(Remote Authentication Dial-In User Service) 1812
C-panel(web hosting control panel) 2082
WHM(Web Host Manager) 2086
WHM-SSL(Web Host Manager) 2087
Webmail (web-based email accounts) 2095
SSLWebmail- (web-based email accounts) 2096
Plesk over HTTPS(Hypertext Transfer Protocol Secure) 8443
Plesk over HTTP(Hypertext Transfer Protocol) 8880
AIM(AIM)  5190