Pixels- a minute area of illumination on a display screen, one of many from which an image is composed

Image resolution– a minute area of illumination on a display screen, one of many from which an image is composed

Megabyte- a minute area of illumination on a display screen, one of many from which an image is composed

Megapixel – a unit of graphic resolution equivalent to one million or (strictly) 1,048,576 (220) pixels.

Gigabyte- a unit of information equal to one billion (109) or, strictly, 230 bytes.

jpeg- a format for compressing image files.

raw-  a file that contains minimally processed data from theimage sensor of either a digital camera, image scanner, or motion picture film scanner.

tiff- The ability to store image data in a lossless format makes a TIFF file a useful image archive, because, unlike standard JPEG files, a TIFF file using lossless compression (or none) may be edited and re-saved without losing image quality. This is not the case when using the TIFF as a container holding compressed JPEG.

PNG- (pronounced ping as in ping-pong; for Portable Network Graphics) is a file format for image compression that, in time, is expected to replace the Graphics Interchange Format (GIF) that is widely used on today’s Internet.

Histogram- is a graphical representation of the distribution of numerical data. It is an estimate of the probability distribution of a continuous variable.

Aperture– a hole or an opening through which light travels.

Shutter speed- the length of time when the film or digital sensor inside the camera is exposed to light, also when a camera’s shutter is open when taking a photograph. The amount of light that reaches the film or image sensor is proportional to the exposure time.

Depth of field– the amount of distance between the nearest and farthest objects that appear in acceptably sharp focus in a photograph.

Noise– The occurrence of color dots or specks where there should be none.

Lag time– Refers to latency, or lag measured by the difference between the time there is a signal input, and the time it takes the input to display on the screen.

Hot shoe- A mounting point on the top of a camera to attach a flash unit and other compatible accessories.

Fisheye- A lens of small focal length, having a highly curved protruding front element, that covers an angle of view of almost 180°.

Aperture priority- a setting on some cameras that allows the user to choose a specific aperture value while the camera selects a shutter speed to match, thereby ensuring proper exposure

Shutter priority- a setting on some cameras that allows the user to choose a specific shutter speed while the camera adjusts the aperture to ensure correct exposure.

Bitmap- mapping from some domain (for example, a range of integers) to bits, that is, values which are zero or one. It is also called a bit array or bitmap index.

White balance- the process of removing unrealistic color casts, so that objects which appear white in person are rendered white in your photo.

Exposure-the act of exposing, laying open, or uncovering:

Watermarking- a kind of marker covertly embedded in a noise-tolerant signal such as an audio, video or image data. It is typically used to identify ownership of the copyright of such signal.

Optical Zoom- allows you to zoom in (or out) on the subject in the LCD or viewfinder. This will enable you to get a closer view of the subject before taking your picture.

Macro ~ a lens suitable for taking photographs unusually close to the subject.

Telephoto ~ a lens with a longer focal length than standard, giving a narrow field of view and a magnified image.

Wide Angle ~ (of a lens) having a short focal length and hence a field covering a wide angle.

DSLR ~ A digital single-lens reflex camera (also called a digital SLR or DSLR) is a digital camera combining the optics and the mechanisms of a single-lens reflex camera with a digital imaging sensor, as opposed to photographic film.

Digital zoom: is a function of a digital camera used to make the image seem more close-up.Digital Zoom on a digital camera works the same as cropping and enlarging a photo in a graphics program.

bracketing: place (one or more people or things) in the same category or group.

light meter:an instrument for measuring the intensity of light, used chiefly to show the correct exposure when taking a photograph.

Image stabilization: (IS) is a family of techniques used to reduce blurring associated with the motion of a camera or other imaging device during exposure.

Dynamic range-,is the difference between the smallest and largest usable signal through a transmission or processing chain or storage medium. It is measured as a ratio, or as a base-10 (decibel) or base-2 (doublings, bits or stops) logarithmic value.

Digital negative- (DNG) is an open lossless raw image format written by Adobe used for digital photography. It was launched on September 27, 2004.

Exposure compensation- Exposure compensation is a technique for adjusting the exposure indicated by a photographic exposure meter, in consideration of factors that may cause the indicated exposure to result in a less-than-optimal image1.