Calibration is the process of adjusting a television's brightness, contrast, colour and other picture settings so the displayed image matches an accurate reference rather than the often oversaturated, overly bright settings many televisions use by default in shops. A well calibrated picture aims for correct colours, natural skin tones and balanced contrast rather than simply looking punchy on a showroom wall.
Calibration ranges from simple steps almost anyone can do, such as selecting a more accurate picture preset and adjusting brightness for room lighting, to professional calibration using specialised measuring equipment and software to fine tune the television precisely, sometimes for a specific room's lighting conditions. Many televisions also include preset modes named for calibration standards that come close to an accurate picture without any adjustment at all.
For most households, choosing an accurate preset and adjusting a few basic settings for the room gives a large improvement over factory defaults, while full professional calibration mainly benefits viewers who want the most precise possible result, for example for critical film viewing. See our guide to TV picture settings for a practical starting point.