Li-Fi is a new method of delivering data. It uses the visible spectrum rather than radio waves. For the firt time, this new breakthrough technology has been tested in a working office. The Li-Fi system uses standard light-emitting diodes (LEDs) to transmit electronic data signals, which will enable users to access the internet through the ordinary lighting systems in schools, workplaces and homes. This revolutionary invention has the potential to bring cheap, energy efficient and super-secure wireless access to the world. Li-Fi is a wireless technology that transmits high-speed data using visible light communication (VLC). With scientists achieving speeds of 224 gigabits per second in the lab using Li-Fi earlier this year, the potential for this technology to change everything about the way we use the Internet is huge. And now, scientists have taken Li-Fi out of the lab for the first time, trialling it in offices and industrial environments in Tallinn, Estonia, reporting that they can achieve data transmission at 1 GB per second - that's 100 times faster than current average Wi-Fi speeds. The technology uses Visible Light Communication (VLC), a medium that uses visible light between 400 and 800 terahertz (THz). It works basically like an incredibly advanced form of Morse code - just like switching a torch on and off according to a certain pattern can relay a secret message, flicking an LED on and off at extreme speeds can be used to write and transmit things in binary code. The flickering of light will not disturb us, because our eyes won't notice the fast flickering. The most significant advantage is the speed that the technology offers. Researchers have achieved speeds of 224 gigabits per second in lab conditions.