Why are we used to driving on the right side? What is the use of the small pocket inside the jeans pocket? People tend to ignore familiar things around them, like desk lamps that are turned on and off on the table, and few people pay attention. But if you pay more attention, it seems that most of the area illuminated by the lamp is circular.

Why is it round? From the candle kerosene lamp to the later bulb lamp, the light of the table lamp diverged from a point light source to form a circular outline. People often buckle the lampshade on the table lamp, so that most of the light emitted by the table lamp is Round .