NetSend
NetSend was a network messaging utility included with early versions of Microsoft Windows, specifically Windows 95, 98, and NT. It allowed users on the same local area network (LAN) to send short text messages to each other. The utility was accessed through a graphical user interface where users could type their message and select a recipient from a list of available computers on the network. Upon sending, the message would appear in a small pop-up window on the recipient's computer screen.
While functional for its time, NetSend was a very basic tool. It lacked any form of encryption,
Due to its limitations and security concerns, NetSend was deprecated by Microsoft and removed from later versions