It is possible in 31 for Windows to play with other human players over the Internet. A maximum of 4 players is supported.
At the start of the game one of the players must host the game, the others can join. To be able to join a game the other players must know the hosts' IP address. If you firewall prevents you from connection to the host, try to open portnumber 10033. On this port the hosts' 31 for Windows will listen for games.
During the game the players can send messages by pressing on the button with the text icon on it. A window will appear in which you can type the text you want to send. When the 'hide'-button is pressed the window will disappear again.
When one of the human-players has lost, he can leave the game without causing any problems for the other players. He can also keep watching to see how the game develops and who will win.