Beginning January 1, 2014, traditional 40- and 60-watt incandescent light bulbs may no longer be manufactured or imported. However, stores may continue to sell them until the supply runs out. The 75- and 100-watt bulbs have already been phased out.
Traditional incandescent light bulbs are being phased out for more energy-efficient bulbs, such as compact fluorescent (CFL) and light-emitting diode (LED) bulbs.
But if you have old light fixtures that can’t use CFL or LED bulbs, you had better stock up while stores still have a supply of the traditional bulbs. (Most CFL bulbs cannot be used in fixtures that have a dimmer switch or a light sensor that automatically turns on and off. You can use LED bulbs for these purposes, but they may not fit in your fixture and they are still very expensive. Prices should begin dropping in 2014 or 2015.)
See advice for choosing light bulbs for help in choosing among the various types.