You may have been purchasing the same types of incandescent light bulbs for the past 10, 20 or 30 years. The pear-shaped light bulb was your only choice for most of your life, although in recent times CFL light bulbs became an energy efficient alternative. During the past decade, LEDs have taken over as the light bulb of choice because of their long-term use and environmentally friendly choice. How do you know which 40W LED light bulb is the right choice for you?