JPEG Lossy compression, good for photos, small file size, widely compatible.

HEIF Lossy compression, more efficient than JPEG, better quality at smaller file sizes, becoming more common (e.g., iPhones).

TIFF Lossless compression (or uncompressed), high quality, large file size, used for archiving and professional printing.

*RAW Minimal processing contains all data captured by the camera sensor, large file size, requires processing, maximum editing flexibility.

DNG Adobe’s open-source RAW format aims for standardization, similar benefits to other RAW formats

PNG Lossless compression, good for graphics, transparency support, larger file size than JPEG for photos.

GIF Lossless compression, limited color palette (256 colors), supports animation, small file size, good for simple graphics and animations.

BMP Uncompressed, large file size, simple format, rarely used.

PSD Adobe Photoshop’s native format supports layers and editing features, large file size, requires Photoshop to open fully.

1. Lenses refract light.
2. Convex lenses converge light.
3. Concave lenses diverge light.
4. Focal length measures a lens’s power.
5. Diopters quantify lens power.
6. Lenses form images.
7. Images can be real or virtual.
8. Real images can be projected onto a screen.
9. Virtual images appear behind the lens.
10. Lenses correct refractive errors like nearsightedness and farsightedness.
11. Cameras use lenses to focus light onto a sensor.
12. Telescopes use lenses to magnify distant objects.
13. Microscopes use lenses to magnify tiny objects.
14. Lenses are made of glass or plastic.
15. Lens shape determines its focal length.
16. Aberrations can distort images formed by lenses.
17. Anti-reflective coatings reduce reflections on lenses.
18. Fresnel lenses are thin and lightweight.
19. Contact lenses rest directly on the eye.
20. Zoom lenses have variable focal lengths.