YouTube one of the best and popular video sharing site is down today with giving 500 Internal server error. The reason for downtime is not officially known and we will keep you updated with the latest development on this downtime.
You can check if YouTube is down using DownForEveryoneOrJustMe.com. If this service itself goes down, you can use alternative! 
Update 1: YouTube is now giving error : Http/1.1 Service Unavailable
Update 2 (added by rahul): YouTube is now giving 502 server error. (What does this error code means?)
Update 3 (added by rahul): YouTube must be down everywhere in the world.
We just checked HTTP headers and found that YouTube is returning 503 server error and server in this case was NS_6.1, i.e. netspace on amazon s3 cloud server. In first screenshot, server signature was Apache.
This may mean that as Apache severs went down, our last request was redirected to backup or another mirror. unfortunately which is also down.
Update 4: DownForEveryoneOrJustMe.com says YouTube is down everywhere. (See screenshot below)
Update 5: Finally, YouTube is back. Hurry!
Internal server error 500
However you can still watch the embedded videos by clicking on them.
wow thats true, i was watching this embedded video and didnt realise the site was down.
As expected ‘Service Unavailable’ is now one of the trending topics of twitter
Lol yea, something interesting. There has been thousands of tweets about it.
Glad it i8s back.. Can’t live without Youtube :p
Down again!
Videos down? Error 500?
mine is down now i need youtube so bad right now.
that s strange how could great site like youtube get server errors they should care more about their servers
I’ve never seen this before!? I mean, isn’t youtube owned by google? I’d have thought that they had enough redundant systems in place to last 1000 years. If you ask me, youtube is overutilized and underpowered. I can’t tell you how many times downoads of videos hasn’t worked very well. In any case, it’s down right now… Maybe it’s on purpose to chase away some hacker or something…