I want to know the diffrence between hdmi and display port

It's a fairly technical explaination. Google/wikipedia is your friend.

they both send audio and video data over the same cable

you have two ways of doing the same thing basically

Which one is better for 3d and 120hz gaming
Btw i use external audio not through hdmi

I'd say HDMI is better for 3D 120Hz gaming just given the fact it's the industry standard and display port is pretty much an Apple thing.

Best answer selected by Youssef amr.

Heres a decent read as well Yousset amr. It'll help  

http://www.techradar.com/news/computing/hdmi-vs-display...

Thanks bro  

I read it and it realy helps
I found that speed of hdmi can be maxed at 10.28gb/s and DP 17.28gb/s so DP is more faster when playing of high resoulotion games

True. But don't confuse speed with what it supports  . Personally.. I would suggest HDMI only because it's more common and cheaper. Most monitors Ive seen (unless you already have one) that support Display port are rather expensive.

But back to the point. Hdmi max's out at 10.28 gb/s DP 17.28 gb/s.
Now lets see what stuff actually uses... So im going to use Vudu as an example (similar to netflix) Per Wiki http://en.wikipedia.org/wiki/High-definition_video It's total bit rate/bandwidth at (max supported res) 1,920×1,080 is only 4.5Mbits/s.

Now... I'm no expert.. I'm sure there are more qualified video gurus on these forums. But from my understanding you won't get anywhere close to maxing out hdmi with these resolutions unless you had tons of screens or a crazy high res. At which point your much more likely to max out your machines hardware capabilities way way before reach the limits of what hdmi can support. Maybe in 2025 when were all gaming on crazy resolutions will this become a true factor.

Still like to hear what some of the video experts have to say about it thou.  

^ this.

You, with a less than a million dollar system, will never come close to hitting peak transfer of either cable