LCD or Plasma monitors are listed with a "native resolution" according to the size of the screen. A resolution number tells you how many vertical and horizontal pixels are available to display your images or text. If your screen's native resolution is 1280x1024 and you decide to change that (because the text is too small - see How to increase text size to fix this problem) resolution to something smaller, like 1024x786, this forces fewer pixels to do the work of displaying images on your screen, thus images are stretched and text is blurry.
Free 3D wallpaper tip: What is my screen resolution?
On a Mac
First we should state the obvious: Most Mac people do not need assistance, this is a fact. HOWEVER, having admitted the previous statement as a life long pc user and having repaired many of them, I must also disclose there are some Mac users that do need assistance - such as the newbies, as I once was!
* Click the Apple menu at the top of your desktop > System Preferences > Displays > view resolution
