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Look around. An electric light probably illuminates the room you’re in. Perhaps the space contains a chair or a desk. Maybe there’s a laptop or tablet in view.
If you’re at home in the kitchen, you may see a box of juice on the counter. If the TV is on, you might see images and hear voices or music. These are things most of us take for granted. But all these things — every single one of them — is the solution to a problem and the end product of the engineering process.