You can communicate with other Pathagoras users by clicking the Send Message button on either of the Network screens. When you do so, you will see a screen that looks like this:
You can select a recipient -one, several or as shown above, 'all' registered users. (You can also choose to send a copy to yourself.)
You can select one of the pre-composed messages and/or compose your own message.
The next time a user tries to access a Pathagoras feature, a screen will appear on the user's computer announcing that 'You have a message from Xxxxx.' The user can accept the message or come back to it when more convenient.