Iso speeds

Digital Single Lens Camera + other cameras

 The basic operation of a DSLR is as  follows: for viewing purposes, the  mirror reflects the light coming  through the lens upwards at an  approximately 90 degree angle. It  is then reflected by the pentaprism  to the photographer's eye. During  exposure (when the photograph is  taken), the mirror swings upward,  and a shutter opens, allowing the  lens to project light through the  aperture onto the film / sensor.Compact camera:A point-and-shoot camera, also called a compact camera, is a still cameradesigned primarily for simple operation. Most use focus free lenses or autofocus for focusing, automatic systems for setting the exposure options, and have flash units built in.SLR (film)A single-lens reflex camera (SLR) is a camera that typically uses a mirror and prism system that permits the photographer to view through the lens and see exactly what will be captured.

Medium format

The size of the imaging sensor comes into play in the final quality of the photo. I'd rather have a 20 megapixel medium format camera than a 30 megapixel 35mm based DSLR because the physical sensor is much larger. The larger the sensor the higher the quality.

Large format

The exposure triangle

The exposure triangle                                           

Shutter speed 
Also so known as exposure time it is the length of time
the camera shutter is open to the exposure of light
if the shutter speed is fast it takes a still image
a slow shutter speed creates more of a motion blur

ISO
In Digital Photography ISO measures the sensitivity of the image sensor. The same principles apply as in film photography – the lower the number the less sensitive your camera is to light and the finer the grain. Higher ISO settings are generally used in darker situations to get faster shutter speeds.

Aperture
Aperture is the depth of field. Lower the number the more blur. higher number more depth of field 

The exposure triangle is the the three main elements of exposure, they're shutter speed, ISO and Aperture