To help you understand better how the 123WebMessenger works, four users' profile pages are mixed together on one page, but please bear in mind that's 4 different screens on 4 computers.
The friends list of each user contains the other 3, click the "1to1 chat" button to invite one of the users and an invite box will popup on his/her window as an alert, then he/she can decide to accept or decline the invitation.
Quick Tutorial
to Add 123 Web Messenger to Your Website 
