What is Aperture in photography?

Aperture is the size of the hole in the lens that lets the light pass through and hit the sensor.

The bigger the hole, the more light it lets in.

Aperture is measured in a system called the f stop system. This is a numerical system that describes how big or how small the hole in the lens is. A smaller number describes a bigger hole, whereas a larger number describes a smaller hole.

For each number on the scale, the lens lets in double the light or half the light.

For example, when you increase your aperture from f/4.0 to f/2.8, you double the amount of light hitting the sensor. Or, when you go from f/4.0 to f/5.6, you cut the amount of light hitting the sensor in half.

Aperture is also the setting on your camera that determines how much of your picture will be in focus.

The smaller the number, the less will be in focus; the larger the number, the more will be in focus.