The greatest technological breakthrough in electronics is the digitization of analog signals. Analog information (represented by a fluctuating wave) is converted into digital information (represented by ones and zeros, or bits). This major breakthrough has led to the advancement of satellites, space research, computers, Internet, and has also shown its usefulness in consumer electronics thru CDs, DVDs, DVRs, HDTV, MP3s and digital cameras.

Digital camera converts light waves into bits and bytes
A digital camera has a lens by which the image is focused, a shutter that allows light to enter into the camera for a split second, and an aperture, which determines how much light, will enter the camera. After the light enters the camera, the image is not captured on film, but on an image sensor.

An image sensor is a semiconductor, an electronic device made up of photosites, which measures the intensity of light. Digital cameras generally use CCD (Charge Coupled Device) image sensor. Some digital cameras also use CMOS (complementary metal oxide semiconductor) or Foveon image sensors. When light comes in contact with the image sensor, it is converted into electrical analog signals, which are subsequently amplified and transmitted to an A/D (analog to digital) convertor. The A/D convertor converts the analog signals to digital binary numbers, which are then processed by a computer chip inside the digital camera body. The digital binary numbers are then stored on a memory card in bits and bytes.

Digital camera processes color by using red, green, and blue colors
Photosites can measure light intensity but not color. Hence, a coloured filter, which is either red, or green, or blue, covers each photosite. These three primary colors can combine to produce any color, including white. The human eye is twice sensitive to the green color hence green is twice in number than red or blue. This formation of the color filters is known as a Bayer pattern. This Bayer pattern covers millions of photosites in the image sensor, with each color occupying a single photosite, known as a pixel. The amount of detail that a digital camera can capture is directly proportional to the amount of pixels it has. The number of pixels determines the quality of the picture and is known as resolution. Professional cameras have more pixels and so a higher resolution. The resolution also depends on the quality of the lens, besides the number of pixels in the image sensor. Digital camera reviews state that high-end cameras support 12 million pixels, whereas professional cameras can support 20 million pixels.

The computer chip analyses the pixel color with respect to its neighboring pixels and produces a composite color. For example, if a red pixel is surrounded by green and blue pixels, then the red pixel must be white, as white is the combination of red, green, and blue. This technique of arriving at a composite color is known as demosaicing. After demosaicing, the image is adjusted according to the preset settings of the camera, like adjustments for color saturation, contrast, and brightness. Professional digital cameras also have a sharpening algorithm that enhances the clarity of the image by showing more details.

Saving the digital camera image as .jpeg, or .tiff, or RAW data
Before the image is saved on the memory card, it is compressed (excludes surplus data, which is lost) by a compression format like JPEG that reduces the file size. Since the surplus data is lost, JPEG compression format is also known as a lossy format. Professional digital cameras have the option of saving the image as TIFF files or RAW data. TIFF files are uncompressed files, whereas RAW data is the original photosite data without any adjustments or demosaicing. The digital camera photo can be transferred to the computer via the serial port or the USB port or the FireWire port or Bluetooth. Wireless connectivity can also be done via WiFi. In case of RAW data, the file size is huge and it takes a lot of time to transfer into the hard disk of a computer. Once transferred into the computer, the digital camera photo can be fine tuned by image editing software as per individual needs. Thereafter, the image is saved in any of the storage media available along with the computer, like hard disks, CDs, or pendrives. The digital camera photo can also be printed or sent as an email. More improvements in the digital camera technology is going on and is featured in the latest models of digital cameras.