Shortcuts for copying files:

To copy a file from one place to another on the same disk, hold down the option key while dragging. This leaves the original file in place while copying it to a new location.

Highlight the file (click on it once), press command + C, select (highlight) the disk or folder you want to copy the file to, then press command + V (these commands are listed under the Edit menu).

The Dock is your handy way to get around in OS X, so you might as well have it work for you.

Not quite sure what all those things in your Dock are? Just let your mouse hover over an icon for a few seconds, and you'll get a pop-up telling you exactly what you're looking at.

Is your Dock full of default icons that you don't use much? No problem, just click and drag the icon right off the dock, and it's gone - of course, the application the icon went to is still on your harddrive, and you can always add it back later if you have the need.

Are there applications or folders that you use all the time? Add them to your Dock. All you need to do is locate the folder or application in the Finder, then drag it over into the Dock.