After having cooked or steamed rice for decades without any problems in a pot, I recently was surprised that many Chinese I talk to don't know how to do that. They need a rice cooker. These are electric appliances, which do absolutely nothing else, than what you do in a normal cooking pot. Some of them have some digital functions and beep around and flash some LEDs. Mainly they just control temperature and time. Some of them also allow steaming. But still on first sight rice cookers seemed to me as completely obsolete.
But I was wrong. Rice cookers in China reach back to a time in which many people were still cooking on a coal fire - actually, many still do this today. As this was the only fire place which can heat a Wok to cook other things than rice, it was convenient to have a self sustained rice cooker, which could do the job in any corner where there is an electric plug. Also, many more modern electric and gas stoves actually only have 2 fires, and not 4. So, again a rice cooker helps a lot to keep these for cooking other dishes than rice.
Rice cookers go back to 1937 where they were used for mobile kitchens in the Japanese Army. In 1945 Mitsubishi brought the first civil electric rice cooker to the market and in the 1950s Toshiba followed with the first fully automated rice cookers.
Interesting. But having a gas stove with 4 fires, I stay with my pot for now.