How does a Digital Camera make a picture?

Hey folks! Generally, in compact cameras, everything is automatic. You just point and shoot. This limits the creativity of the photographer and hence all the images look the same. In SLR cameras and certain models of compact cams, there are manual modes. In this mode, the photographer can control various functions of the camera manually to get the right look.
To understand what you can achieve, let me take you through what actually happens when you click a photo with an automatic camera. In a traditional film camera, you load the roll of film and start shooting. In this roll, there are usually around 36 exposures. Or you can make 36 photos with one roll of film. Each light-sensitive area is aligned, using an automated motorized mechanism, with the focal point of the lens. This area is approximately 35mm wide and 24 mm high. Hence the film used is called 35mm film.
Since this part of the film is light-sensitive, there is a curtain in front of it and a shutter that opens and closes to let light in. It is closed at all times except when you click.
Now, in Digital cameras, there is no film. Instead there is a light-sensitive sensor in the same place. The sensor has electronically charged pixels that grab light data as soon as light enters it just like how the chemicals of the film would react to light. When you "click", you are pressing the shutter release button. The built-in light meter will analyze the amount of light on the subject, and then rapidly open and close the shutter to let the right amount of light fall on the sensor. This is how the pixels grab all the data and convert it into an image. This is stored in a compressed form as a JPEG file. This file is displayed on the LCD screen of your camera.
That is what happens in a fraction of a second when you click a picture.
Hope it was informative! Next time, i will explain what are shutter speeds, aperture, ISO, White Balance, etc.

Cheers!