A fluorescent tube is a type of lamp that illuminates by using electricity to activate and agitate mercury vapor. When this happens, the atoms of mercury that is in the tube actually emit ultraviolet light. This cause the light to fluoresce and create actual visible light that we can see and use. One of the great things about these tubes is that they are able to convert electrical power into light far more easily than an incandescent lamp is able to do. What does this mean for the person who uses the light? It means a savings in the cost of electricity. This is one of the big reasons that you often see these types of lamps in use in office buildings. Even though there is a higher initial cost, you will find that it balances quickly, and then the real savings begin.
Of course, there are a few disadvantages as well. For example, the lights need to have proper recycling since they contain mercury. In addition, they can be prone to flickering, which can be an annoyance for some people.