What is a USB Smart Button?

Simply put, a USB Smart Button is press button that is connected to the computer by a USB cable.

When connected, they usually have a LED light inside to draw subtle attention to it.

When pressed the button send a keyboard command to the computer to open a web site (internet), or a an intranet (closed company network).

USB buttons now come with either one link, or dual links. Some models come with a USB hub. 
The Eco-button has additional power saving features installed in it.

Here is a simple presentation on how they work.

They are keyboard emulators, the computer recieves a command just it would from a keyboard.  This means they can not hold viruses, nor be infected, making them completely safe for your users.