Write a simple Client$/$Server application where the server receives a message $($a string of characters$)$ sent by the client over the network and simply sends it back to the client. Here, you need to write two separate programs: the server program which will run on one computer and the client program which will run on another computer in the network $-$ or on the same computer if you cannot have access to a second Windows computer.

The server program is started first and all it does is wait for a message from the client. When the client sends a message and the server receives the message, it simply sends it back $($echoes it$)$ to the client which will display it$.$

Write a simple Client$/$Server application that allows the user on the client computer to send or receive $($upload$/$download$)$ a file to$/$from the server computer.

Write a simple Chat application that allows two users on different computers on the network to exchange small chat messages.