How is popcorn made?

Childhood was in the 80's when material things were relatively less abundant, and for me as a child, the food I remember most is popcorn.

An air furnace was roasting under a charcoal fire, and the craftsmen shouted as they turned the furnace. Children from near and far come from all directions with their own kernels of corn, blinking and staring at the stove. With a burst of aroma wafting, the craftsman picked up a nail hammer and gently knocked against the pot, only to hear a popping sound, bursting kernels of corn rolled.

It goes without saying that children's mouths have been watering for a long time.

Growing up, with childhood memories of popcorn is no longer the sweetness of the year.