Telnet has now become almost an obsolete term which has traces back in 1969 when it was initially developed. In 1973 it was a general utility used to talk with other computers and machines. At that said time the systems were mostly connected through the local area network. Telnet is defined as a network protocol used over the internet or local area networks which provides bidirectional interactive text-oriented communication facility using a virtual terminal connection. This is the telnet original definition as defined by Wikipedia.
The telnet facility was later being replaced by other
Protocols because It does not secure any passwords or other sensitive information which can be manipulated by anyone with having controls over the connecting devices like routers etc. All the information sends and received through telnet is not encrypted so the passwords and other sensitive details were subject to sever vulnerability means that they can easily be stolen.
SSH protocol was introduced later and it was far more secure than this telnet provided access to command line interface on a remote host. Because of serious security concerns using telnet over an open network such as internet its use has waned significantly in favour of SSH. However, even if it was being replaced through secured protocols but it is still in use by many applications and by many developers/administrators.
Even this telnet does not seem to be secure and it is a text-based protocol only however it is still used for configuring the network devices even modern routers connected via LAN or internet services. This means that the telnet utility can still be useful in configuring any network device even in this modern era. There are still many online chat services which are fully based on the telnet utility where the users enter through the command line user interface to chat with another user residing any other part of the world. These chat software(s) were once one of the most favourite hobbies of individuals living in developing countries.
Another important use of this telnet utility is that it is being used by the administrator to access any specific computer remotely to fetch any specific data with all the privileges of that specific computer user. Although there are many other computer programs like FTP protocol etc can be used to access the files at any computer system however through telnet the admin can log into the system very similar to the user of that particular system.
So despite being security concerns, this telnet utility is still being used widely in the computer networking industry. The individuals with Cisco certifications also have their hands on this command line interface through which they access many computer systems and troubleshoot them. This telnet utility is basically a language which was initially developed with a purpose to send and receive data information between two machines with at least one live user in this whole process. It is a text-oriented protocol which does not support any fancy graphics or user interface, neither we can transfer files through this protocol.
Summarizing to an end this telnet utility has its own pros and cons as well as it applications in various field of computing however it is still as important as it was in the earlier days when the computers were in their state of infancy but now with the technological and digital revolution, they have changed the whole world. Now almost every person, every organisation, every business is shifted to computers. Every process of our daily routine is being shifted to the computer where the work is done in a more efficient way as it was done manually in the past