Read the following paragraph: "The invention of the light bulb by Thomas Edison in 1879 changed the world forever. Before light bulbs, people relied on candles, oil lamps, or gas lights, which were dim and could be dangerous. The light bulb allowed factories to stay open later, made streets safer at night, and transformed how people lived in their homes. Today, we continue to improve this technology to make it more energy-efficient." What is the main idea of this passage?