If you are having trouble with a specific term, or would just like a little more information, use this glossary as a basic reference.

Auto Exposure
The camera automatically calculates the best aperture-shutter speed combination for lighting conditions. Typically, options include program or full auto (the camera selects aperture and shutter speed), aperture priority (user selects the aperture and the camera selects the shutter speed), and shutter priority (the user selects the shutter speed and the camera selects the aperture) modes.

Auto White Balance
The camera automatically sets white balance to match the true color of the subject.

Auto Focus
The camera focuses automatically.

Built-in Memory
Many inexpensive digital cameras store pictures in a built-in memory buffer. Once the buffer is filled, the images must be downloaded to a computer before more pictures can be taken.

CCD
Charge Coupled Device; the imaging sensor that actually captures the picture.

Compatible Memory Type(s)
Digital cameras use a variety of different types of memory storage media. Most cameras accept only one type, and the different types are not interchangeable. Compact Flash is the most common and most popular type.

Compression
Compression is the process of compacting digital images using software algorithms to subtract data. Smaller image files are easier to store and manage.

Digital Zoom
Digital zooms magnify a small area at the center of a digital image. Digital zooms degrade image quality, cause color to fade, and increase digital "noise".

Display
Camera display is usually visible on the back of the camera on the LCD screen or in the viewfinder. The display allows digital camera users to review important information such as battery status, number of images, modes, etc.

Effects
Effects are automatic modes that allow you to add creative effects to your pictures, such as converting them to black and white or sepia tone.

Exposure compensation
Allows users to intentionally under- or over-expose a shot to achieve a particular effect.

Exposure Modes
Most digital cameras allow the user to select from a variety of operational modes-typically Auto, Program, Aperture Priority, Shutter Priority, full manual, and scene modes, which automatically maximize settings for specific types of images, such as portrait, close-up, or landscape.

Exposure Value
An arbitrary method of incremental measurement that can be adjusted on some digital cameras for more precise exposure control.

Flash
Most digital cameras provide an on-board or built-in flash unit to help balance lighting for low light and night photography situations. More complex digital cameras offer built-in flash units with more comprehensive flash options like red-eye reduction, second curtain synch, and fill flash. Some digital cameras provide an auxiliary hot shoe to permit the use of external flash units.

ISO Film Speed Equivalence
ISO (International Standards Organization) is a measure of light sensitivity used by traditional film photographers. An equivalent measurement system in digital cameras allows photographers to double or halve light sensitivity around a basic value (typically ISO 100). A higher ISO (200, 400, 800, 1600) rating means the camera will allow photographers to adjust the sensitivity of the CCD for low light situations.

JPEG
JPEG (Joint Photographers Experts Group) is the standard file format for digital images. JPEG images are compressed (on-board software shrinks the file size of the digital image). JPEG is the most common file storage format for digital photography.

LCD Screen
The Liquid Crystal Display (LCD) is the small screen on the rear of many digital cameras. The LCD is used as a viewfinder, to compose images and to check images after exposure. You can use the LCD for viewing and editing images. Some models also use the LCD screen for displaying a menu of camera options.

Lithium-Ion
A popular variety of rechargeable battery that retains the ability to charge fully after extended use and can be charged at any time (doesn't have to be fully discharged).

Macro Capability
Some digital cameras have the ability to focus on objects very close to the lens. The ability to focus closer than one foot from the object is considered macro capability. Many digital cameras allow users to focus on subjects at four inches or less.

Manual Focus
Allows camera users to bypass the auto-focus system and manually focus the camera. Good for focusing in low light or focusing in very precise increments.

Megapixel
Digital photos are comprised of pixels. One megapixel is equivalent to one million pixels. Today's cameras are available in one to six megapixel resolution formats. A camera that can capture more megapixels can capture more detail and sharpness in a photo. An image with more megapixels can be enlarged and printed without sacrificing image quality.

Noise
Areas of missing information in a digital image. Digital images are composed of millions of pixels that are captured by a camera using a digital sensor array. Within this device, some pixels may function poorly or fail to function at all, which results in dead or "hot" pixels. "Hot" pixels are bright white, and dead pixels don't show any color. In brightly lit scenes, hot or dead pixels blend into the overall image and effectively disappear. In low light scenes, hot pixels are visible as digital noise-white or brightly colored spots in the image.

Optical Zoom
An optically formulated imaging device with continually variable focal lengths. Allows users to vary subject magnification without changing position, as with the telephoto zooms used on interchangeable lens film cameras.

Pixels
The individual picture elements that make up a digital display. The more pixels, the greater the detail and sharpness of the display or the image.

Resolution
Resolution is a measurement of image sharpness and is expressed in millions of pixels, or megapixels.

Saturation
A measure of the level of color intensity. Highly saturated colors may cause images to appear unrealistic.

Scene Modes
Digital camera exposure preset modes that are optimized for specific types of images, such as sports photography, night shots, close-ups, portraits, or landscapes.

USB (Universal Serial Bus) Connection
Most digital cameras connect to a computer and transfer image files with either a serial connection or a USB connection. Serial connections are generally slower than USB connections. USB connections may not be found on older computers

VGA Resolution
VGA is an abbreviation for video graphics array, a graphics display system for PCs developed by IBM in 1987. VGA resolution is 640x480 pixels (about 300,000 pixels). All PCs made today support minimum VGA resolution for e-mail images.

Video Out
Connection format that allows the user to view digital pictures on a television or record them to a videocassette.

Zoom Range
The focal length range from the near (or wide) end of the zoom to the far (or telephoto) end of the zoom. Zoom range is also measured with X, representing a multiplier. For example, a 35-105mm zoom is also listed as a 3X zoom.