Aspect Ratio

Aspect ratio is the width-to-height ratio of a display, expressed as W:H. Common ratios: 16:9 (standard widescreen, most monitors and TVs), 21:9 (ultrawide, for productivity and immersive gaming), 32:9 (super ultrawide), 4:3 (classic, mostly obsolete), 3:2 (some laptops like Surface). The aspect ratio determines what content fits natively without letterboxing or stretching. Ultrawide monitors (21:9) are popular for productivity (multiple windows side by side) and immersive gaming.