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 image