Have you ever wanted to “zoom into” your Mac’s screen to get a closer look at text or an image? If you have Mac OS X, it’s very easy. On a Mac with an external mouse, hold down the “Control” key (located under the shift key and marked “ctrl” on many keyboards) and roll forward or backwards with the mouse’s scroll wheel.
On a Mac laptop with two-finger scrolling enabled, hold down the Control key and mouse up and down while holding two fingers on the touchpad. You can enable two-finger scrolling on most Apple laptops running 10.4 or 10.5 in System Preferences > Keyboard & Mouse.
Notice how the screen will stay zoomed in and follow your mouse around until you zoom all the way out. Pretty cool! It also makes a fun late-April Fool’s Day joke to play on Mac newbies.