How can I move singleplayer worlds on Minecraft to another computer?

So, If on one computer I make a singleplayer minecraft world, can I get it onto another computer? If so, how and please give detailed instructions (step-by-step is preferable). If it matters, I'm playing Minecraft Beta 1.8.1.

 Ansver:

okay, this is easier than you think. This is assuming you have Windows.
1. Open run (search for it)
2. type in exactly: %appdata%/.minecraft/
3. Double click on saves
4. Copy world
5. Save it on a flash drive or zip it and send it to yourself
6. Repeat steps 1-3 and put file in there
7. Done
Have Fun!

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Wkhammond is correct. search for %appdata%, go into .minecraft, go into saves, copy the appropriate world onto a flash drive or zip it and upload it as an email attachment, then go to the other computer and save it/extract it into the .minecraft/saves folder there.

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I don't have Minecraft, so I can't be extremely specific but, copy the files from a world folder to a USB. Transfer the USB to the other computer, then put the files into that computer's Minecraft world folder.

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Use the Run tool and type %appdata% and click roaming and .minecraft and saves and copy your world onto the thing you will use to transfer the world. (usb stick, email with attachment, etc)