I went to handy man this afternoon to buy a living room switch and there are many kinds and designs. I really cannot choose so I asked the sales lady for assistance. She then explains the different switch designs that I can choose from. There is the common switch where you just push the button. There is the William J. Newton and Morris Goldberg design where the switch handle does not control the contacts directly, but through an intermediate arrangement of springs and levers. This is also called the toggle switch where it is safe and reliable. This switch produces loud snap when it is being clicked.
There are switches that are not common but existing like the illuminated switch. Maybe some knew about it but I don’t. Anyway, this switch has internal light that you can see in the dark. The internal light source in a single pole illuminated switch derives its power when the switch is OFF from current passing through the external light bulb. There are the mercury switches that are popular in the past. Dimmer switch changes the brightness average of the light so you can control how bright you wanted with the light.