1) telnet is insecure, in that the password you submit through telnet to the target machine travels "in the clear" (ie, legibly). This is an issue because the nature of network traffic is that it passes through a series of intermediate machines on the way from sender to receiver. Software or people at such machines can observe the password.
2) Microsoft has made various small changes to its built-in telnet client from version to version of Windows. Your screen may look a little different than the screenshots below but the basic functionality is the same.
Telnet is a so-called "terminal emulator." It would be nice if you could walk up to the remote computer that hosts your account, sit down at the terminal (monitor), and do your work there anytime you wanted. But you can't. That's what a terminal emulator is for. It emulates (pretends to be) a terminal. You tell it which machine you want to connect to. If that machine offers telnet access, you get the same experience as you would if actually seated at the machine.
The remote computer used by our class does offer telnet access. What's more, a copy of telnet is built into Windows. So now if you have a Windows machine, you have a Unix machine. We set it up that way for this class.
You can't use the remote computer until I give you an account there (although you can get as far as the "login" prompt). But if you want to get the flavor of how you use a remote machine from the comfort of your local one, below are some machines that allow you in even if you don't have a personal account on them. Try it.
Password: none needed.
(The Library of Congress Information Service)
(A Stanford University database)
At the "login:" prompt, type `bbs' and hit enter.
(run by the Iowa Student Computer Association)
In addition to the built-in Windows telnet (which is limited, though probably sufficient for this class) there are quite a few free telnet programs for Windows and Mac that can be downloaded and installed. The one I use and prefer is TeraTerm. Others (some free, some not) are on offer for download at http://tucows.tierranet.com/term95.html.
Below is a sequence of screens captured from my Windows95 machine when I logged in to a remote computer called vlacc.rexx.com.
You can run Windows' telnet program from the Start/Run dialog box.
It shows up on your screen like this.
Use telnet's Connect/Remote System menu option to tell it what machine you want it to connect to.
It gives you the little dialog box below. Type in the name of your desired target machine (vlacc.rexx.com in the example below). Then press the Connect button.
Assuming your machine is internet connected, contact will be made with the remote machine you name, which sends back some text that shows up in your telnet window. It's asking you to log in by giving it your pre-established account name (called a user id in Unix-speak).
After you give it a valid user id, it demands a matching password:
If you give it one, it completes the login process, presenting you with a command prompt that will wait for you to type commands. You are now operating the remote machine. When you want to stop doing so, the Unix command that will end your session on vlacc.rexx.com, and sever the connection with your Windows telnet program, is "exit".
Please don't expect to get this far until I have set up an account and transmitted the information to you (that is, established a user id and password for you on the remote computer for our class and told you what they are).