Notifying other computers when the data on the server changes

Question

Hi. 
Here is my situation. 
We have:

- A server running apache and mysql.
- Several computers on the same LAN as the server
- The server and the other computers all run the same program takes orders and displays current orders
- The server also runs a website that lets users enter orders
The issue is displaying the most current information to all the systems running the program (program is written in c#). 
 I used to just have a timer that refreshed the information every second, but that is no longer a viable solution. 

What I need is to somehow have the mysql table fire a trigger, notifying the server and all the other systems that there is a change in the orders anytime that change occurs.


(UPDATE) 
I've been scouring the internet, and I think what I need are triggers, but I can't find a good tutorial.
 
It doesn't have to be a notification system, if there is a real-time way to always have the most up-to-date info from a table without adding overhead.