A terminal emulation or telnet is a program for TCP/IP networks such as the Internet. The Telnet program runs on your computer and connects your PC to a server on the network. You can then enter commands through the Telnet program and they will be executed as if you were entering them directly on the server console. (More on Wiki)
If you type telnet in your windows console you will see command not found
That's because telnet client is not enabled by default on Windows. Lets see how can we enable it.
To enable Telnet command line utilities:
- Click Start > Control Panel.
- Click Programs and Features.
- Click Turn Windows features on or off.
- In the Windows Features dialog box, check the Telnet Client check box.
- Click OK. The system installs the appropriate files. This will take a few seconds to a minute.
And telnet client should be enable in your windows. You can just type telnet and check. It should open Microsoft telnet client. Or you can try directly connection to a host.
Eg. telnet alt4.gmail-smtp-in.l.google.com 25