What Does http 1.1 Service Unavailable Mean?

I tried to acces my email first and I got "HTTP/1.1 503 Service Unavailable"
Then I tries to access youtube and I got the same "HTTP/1.1 503 Service Unavailable" message.
What does this mean? does this mean the website I'm trying to access is down? Or is there a problem with my internet connection?
What does the message mean?

It's a problem on their website. The message meand the website you're trying to access seems to be down for maintenance. The error http 1.1 Service Unavailable you have seen was probably a bug or a system failure, and the tech guys are trying to take it up again.
So you will have to wait, there is nothing wrong with your computer.
The http 1.1 Service Unavailable message is a server error.

So if I just wait a day or two I should be able to access the site again?

Does It Really Take A Day Or two Because It Happens To me While I Try Logging On to Myspace

i tried 2 to log in myspace and it doesn't let me!!!

Did you wrote something bad or racist? Because it's the block-message.