Flash Video - Default Installation vs Adobe Flash Player?

What's the difference between the default flash playback that comes with a fresh Mavericks / Yosemite installation and the Adobe flash player?

With a fresh Mavericks / Yosemite installation, flash video will play on my MacBook Air. The default flash option doesn't work very well with the firefox flashblock addon though.

If I go to the Adobe website and download and install the adobe flash player (over the default OS X flash option?), it tweaks the flash video / interface slightly and works much better with flashblock.

Does OS X come pre-installed with an Apple version of flash or something? If there are indeed two separate versions, is there a consensus as to which is better?

If somebody could clear this up for me I'd appreciate it.

Thanks

 

Ahh, maybe this is what's happening then. I just assumed it was flash (on Windows nothing will play until adobe flash player is installed). I wasn't aware there was an h.264 version.

That makes much more sense though. Flash always seemed pretty inefficient (on my older C2D MacBook Pro, flash video uses a ton of processing power and fans go crazy) so it makes sense they would use something else when possible.

Anyway, thanks for clearing that up for me.