Standing on this will keep you on dry ground, which is less hazardous than damp concrete. You also should wear dry, rubber-soled shoes and leave one hand in your pocket to keep from inadvertently becoming a pathway for the electrical current. When replacing lights, don't assume you can install a light with higher wattage. The circuit might not support the additional power demand. You always should confirm the total demand by other lights, receptacles, or appliances before changing an existing fixture.
Electricity is the movement of electrons.
A conductor holds its own electrons loosely, so current can easily pass through. Metals, such as copper wire, are good conductors for carrying electric current. An insulator has tightly held electrons, which means current does not flow through it. Plastic, used to wrap around copper wire, is a good insulator, as is cloth, which was once used for the same purpose. The history of electricity and electrification is full of pioneering scientists, each building on the knowledge of the others.