At most one of the three test images (courtesy of Photodisc) can look decent on your screen, showing convincing skin tones, detailed highlights and shadows, and no overall color cast. If none does, you will do yourself a great favor by calibrating your monitor. If the left image looks best, then your monitor behaves like many do straight from the box: it is way too bright and too blue. Again, calibration is recommended. If the middle image looks best and, what is more, looks good, your calibration is in the ballpark. The right image is there to mimic (on screens with acceptable calibration) how the middle image looks on many uncalibrated screens. Macintosh users are lucky, because an easy calibration tool is built into their System Preferences (under Displays > Color). For PC-users, QuickGamma is a piece of freeware. Serious information on monitor calibration is available, for example, from Norman Koren.