Telnet is a network protocol that allows users to connect to remote computers over the Internet or local networks. It provides a command-line interface for communication, enabling users to execute commands on the remote machine as if they were physically present at that location. Despite its historical significance, Telnet is often considered insecure due to its lack of encryption, making it vulnerable to eavesdropping. As a result, many users have shifted to more secure alternatives like SSH (Secure Shell) for remote access, which encrypts the data transmitted between the client and server.