If your wall clock says something different, then your wall clock is probably right. Computers aren't designed to be clocks, they're designed to be computers, so they don't keep time as well as clocks do. You can adjust the time on your computer to be what your wall clock says.
When it's noon on one place, it's midnight in another.
What this map tells you, is if it's 8pm in England, then you subtract 5 to get 3pm in New York.

The time zones are without taking Summer Time into consideration.
We sent a rocket to the sun with a video camera, so that folks from the web site could have a view of the world from where the sun is. Or you can use the camera that we set up on the moon. Or from any of dozens of orbiting satellites. You can zoom in, rotate the world to see your part of it. If you rotate the world, you'll see where it's just dawn, or sunset. And the camera has a zoom lens, so you can zoom in to be just 10 km away from the point you're looking at. While you're there, you can have a look at the cloud cover right now, and the weather all round the world.
Thanks to the UK Meteorological Office, to Meteo France and the Weather Channel for the above. So, you thought it rains all the time in England?
(c) 1996 Diana the Valkyrie. A hard man is good to beat.