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Short note: Resolution and aspect ratio

Short answer

Resolution is the number of pixels displayed as columns × rows, e.g. 1024×768. Higher resolution yields more detail but requires a larger frame buffer. Aspect ratio is width-to-height ratio, such as 4:3 or 16:9, and mismatch causes stretching.

Write a short note on resolution and aspect ratio of a monitor.

Resolution

Resolution is the number of pixels that can be displayed on the screen, given as columns × rows (e.g. 1024 × 768, 1920 × 1080). It can also be given as pixels per inch (PPI/DPI). Higher resolution means more pixels, finer detail and a sharper picture, but needs a larger frame buffer.

Frame buffer size = width × height × bits per pixel
Example: 1024 × 768 × 24 = 18,874,368 bits = 2.25 MB

Aspect ratio

Aspect ratio is the ratio of the width to the height of the screen (or image). For 1024 × 768 it is 1024 : 768 = 4 : 3. Other common values are 16 : 9 (1920 × 1080) and 16 : 10.

The aspect ratio is also the ratio of the number of horizontal points to vertical points needed to produce lines of equal length in both directions. If the aspect ratio of an image does not match the screen, the image looks stretched or has black bars.

Resizing keeping the aspect ratio: new height = new width × (old height / old width).

✓ Answer checked by Claude Opus 5.5 (high effort)

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