If you are looking to capture PC gaming stuff, and then broadcast/edit it later, I know that *generally* speaking, at least from the crowd that I follow, they use either [url=http://www.xsplit.com]Xsplit[/url] (which has a monthly/yearly license cost, although there is also a free version) or [url=https://obsproject.com/]Open Broadcaster Software[/url] (which is 100% free).

They both have their pro's and con's to each other, but they do both allow local file capture, as well as streaming directly to sites such as Twitch.tv and Hitbox.tv.

Now, if you want to capture *consoles* (new and old) then you will need extra hardware, with something from either [url=https://www.elgato.com]Elgato[/url] or [url=http://www.avermedia.com/]Avermedia[/url]

The console versions have the potential to reduce CPU load, as they will be encoding the stream before it gets to the PC, whilst the PC direct streaming can be a bit strenuous, although with new PC's it isn't really so much of a problem (1280x720 resolution should be easily doable for most current PC's), but the upload speed of your connection will be more of a limiting factor.

Most of the people that I know tend to use OBS on the software side, even if they do use external hardware for their game capture (hey, I watch a lot of people speedrunning computer games, so the hardware is needed for them).

If you have any other questions, I can poke a few of the people I follow to get answers if need be.

I personally use OBS right now, although I rarely do any form of streaming right now.