Frame Pump or CO2?

I've been watching expert village about bike repair and maintenance and there is something called a co2 cartridge that you can use to fill your flat that I've never seen before. How do you use the co2? What's better: the old frame pumps or co2? Why is it better?

I'm still old school and use a frame pump. Flats are inevitable, but relatively few and far between. If I lose a few minutes by using a pump, it's no big deal. Pumps are reliable and you can inflate the tire part way to check and make sure the tire's bead is seated properly before you inflate it all the way. With co2, you only get one chance to fill the tire and if something happens, you're out of luck. And if you're on a long ride and have an unusual number of flats, what do you do if you run out of co2 cartridges? With a pump, you don't have that problem.

as a former owner of 4 frame pumps, and a converted CO2-er, get the CO2. Frame pumps take alot of time and energy, which only adds to the frustration of a roadside flat repair. CO2 is quick, fairly cheap, and very satisfying. You have a small chuck that you screw the CO2 cartridge into. It break the seal, and when you press it onto your valve, it quickly inflates your tire and promptly becomes a very very cold very very empty carttridge. It is lighter, faster, more modern, and very small.

When you get home, deflate the tire and re-fill from a real pump. (i dont know the validity or science of it, but ive been told this and it seems to be true) CO2 will slowly condence lowering the air pressure in your tire over a few days, so refilling with regular "air" will keep you going. Half the size of a cell phone vs. a pump crammed into/onto your frame

The 2 big names in CO2 is Zefal and Genuine Innovations. Ive used Zefals, and they are ok. GI have one called the microflator that is cheap and basic, and works well. for a few extra bucks, you can get the "minichuck" which works even better.

I used to use co2 but have gone back to using a pump after being caught out too many times running out of air on long rides and getting flats. If your out and about and get a flat you may use up the co2 just trying to find the puncture.
You can get super light, small, carbon pumps which can pump up road bike tyres easily, and you dont have to pay a fortune. If weight isn't a problem then carry both just in case you run out of co2.

speed
convenience
size

frame pumps take up more space and is slower in pumping air (higher pressure). CO2 takes up less space and airs quickly. CO2 is convenient but if you don't have enough canisters then you end up with under-inflated wheel. They also produce trash.

I use a frame pump. Mine is only about a foot long and works great; the mounting bracket shares the waterbottle mounts so its not in the way. One year I tried using a CO2 pump and it never worked enough and had a tendency to freeze up.

I still use a pump. If you mess up filling with CO2 you are SOL.