Telnet lacks authentication policies and data encryption.
The Beginning of Telnet
Telnet refers to a data pipe virtual terminal protocol.
It was built as a form of remote control to manage mainframe computers from distant terminals.

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This remote login saved researchers hours of walking each semester.
SSH provides strong authentication and secures encrypted data communications between computers over an insecure connection.
No Graphics Here
Unlike Firefox or Google Chrome screens, Telnet screens are unremarkable to view.

Telnet is all about typing on a keyboard.
It has none of the graphic elements we expect from web pages today.
Telnet commands can be cryptic, with example commands includingzandprompt% fg.
Most modern users would find Telnet screens to be archaic and slow.
Telnet is rarely used to connect computers anymore because of its lack of security.