What is that smokey thing the beekeeper uses to “tame” the bees? Is it CO2 vapor, as I understand beens become docile at colder temps? If not, what is it? Why does it smoke? Is it hot? - Jinx 
My brother (15 years ago, in Russia) used something like a bellows but with a compartment for a smoking agent - specifically we used smouldering pine cones and dry grass. Is that what you’re talking about? Bees hate smoke. However this was mostly for my benefit, since somehow bees recognized him and ignored him anyway.
Beekeeper here.
It is called a “smoker.” It has a bellows and a can (where you build a smoldering fire) and a funnel shaped tip to concentrate the smoke into a stream. There are a variety of fuels you can burn, paper pulp, newspaper, pinestraw being highly favored. And there are some things you avoid using - cedar shavings for instance. You don’t want something too aromatic, or to overuse smoke, because the honey will pick those flavors up.
Why does it work? When bees smell smoke they ‘think’ their hive is on fire and they are about to have to move to a new location and build a new hive. Bees need honey to make wax, and they need wax to set up a new hive. So thinking their hive is about to burn, the worker bees all rush to fill their honey stomachs with honey that they’ll take with them to a new hive location to rebuild. And if they are busy doing that, they are too busy to sting you.
Experienced beekeepers often forego taking their smoker into the bee yard. If you have even tempered bees, and everything is going well for the hive (they have a queen, they have pollen and nectar available to gather), and you are careful not to irritate them with your actions (for example, the smell of a squished bee will make the other bees more agressive) then you probably won’t need the smoker. But all but the most diehard beekeepers will stop and go get their smoker when they run across a hive that isn’t behaving. And some hives are just easily irritable and you learn to always have plenty of smoke on hand to work with them.
-rainy
Carbon dioxide does serve as an anesthetic for bees (and other insects), and will knock them out for a few minutes. But as rainy says, the reason for the smoke is to make the bees docile, not to knock them out.