I think the greatest invention was light bulb. It was invented by Thomas Edison about one hundred years ago. Now after few adjustments we can use it without any effort. It helps us to live when it’s night. We can easily lengthen our day time by using light bulbs. We can stay late if we want to read a book or draw a picture. I’m really fascinated how it works. I wonder how life used to be before Edison invented light bulb. For sure they were going much earlier to bed than we go now. Without any doubt I can say that this invention was a breakthrough in technology.
