Take Manual Control

Aperture is the hole light goes through. A small number like f/2 means a big hole: lots of light and a blurry background. A big number like f/11 means a tiny hole: less light but almost everything is sharp. Blurry background is great for a face; sharp everything is great for a mountain.

Try it at home: In your phone's Portrait mode, slide the blur amount up and down. That is aperture faking it.

Shutter speed is how long the camera's eye stays open. Fast (1/1000 of a second) freezes a jumping dog mid-air. Slow (1/4 of a second) smears motion into streaks — cool on purpose, terrible by accident. Anything slower than about 1/60 needs the camera propped on something.

Try it at home: Photograph a spinning fan twice: once in bright light (frozen blades) and once in a dim room (blurry blades).

ISO makes the sensor more sensitive so you can shoot in the dark. But turning it up adds grainy speckles called noise, like static on an old TV. Rule: raise ISO last, only after you've opened the aperture and slowed the shutter as much as you safely can.

For video, set your shutter speed to about double your frame rate — shooting 24 frames per second? Use 1/50. That gives motion the natural little blur your eyes expect. Too fast and video looks jittery like a video game.

Try it at home: Record someone walking at 1/50 and again at 1/1000. Watch how weird and choppy the fast one feels.