Exposure Triangle
Aperture: Is a hole or an opening through which light travels.Aperture is how opened or closed the lens' iris is. this technique is used to control how much light enter the lens. For example when taking a picture of something, you focus you camera on the bit you want to stand out and the rest of this picture the (background) will be blurry.
I took this picture in Bradgate park. The camera is focused on to the rock, and that's what stands out the most in this picture, the background is all blurred out which then give it a great effect.
Shutter speed: How fast the shutter on the camera goes. Shutter speeds are measured in a amount of seconds. Exposure time is the amount of time the sensor is exposed to the light. Shutter speed is measures in seconds, or in most cases fraction of seconds. The bigger the denominator is, the faster the speed, for example, 1/1000 is much faster than 1/30.
iso: ISO stands for the International Organisation for Standardisation. In photography iso measures the sensitivity of an image and the lower iso the more gainer the photo the less sensitive you camera will be to the light. We can control the ISO to create an image that is correctly exposed, which is not too light and not too dark.