If you are shopping for a new or used digital camera, here is some information to help you compare the latest digital cameras online.

First off, a digital camera (or digicam) is a camera that takes video or still photographs, or both, digitally by recording images via an electronic image sensor. Many compact digital still cameras can record sound and moving video as well as still photographs.

However digital cameras can do things film cameras cannot: displaying images on a screen immediately after they are recorded, storing thousands of images on a single small memory device, recording video with sound, and deleting images to free storage space. Some can crop pictures and perform other elementary image editing.

Compact cameras are designed to be tiny and portable and are particularly suitable for casual and “snapshot” use, thus are also called point-and-shoot cameras. The smallest, generally less than 3/4″ thick, are described as subcompacts or “ultra-compacts”.

Compact cameras are usually designed to be easy to use, sacrificing advanced features and picture quality for compactness and simplicity, while professional cameras can be used for greater versatility.

Also becoming more popular are waterproof and more rugged cameras, which are engineered for extreme conditions.

Compared to traditional cameras which store images on film, digital cameras store images on memory cards. The majority of cards for cameras are known as SD format. A few cameras use some other form of removable storage such as Microdrives (very small hard disk drives), CD single (185 MB), and 3.5″ floppy disks.

Digital cameras have high power requirements, and over time have become smaller, resulting in an ongoing need to develop a battery small enough to fit in the camera and yet able to power it for a reasonable length of time.

Most types of battery for digital cameras conform to an established off-the-shelf form factor, commonly AA, CR2, or CR-V3 batteries, with AAA batteries in a handful of cameras. The CR2 and CR-V3 batteries are lithium based, and intended for single use. AA batteries are the most common. However, the non-rechargeable alkaline batteries supplied with low-end cameras are capable of providing enough power for only a very short time in most cameras, and rechargeable NiMH batteries AA batteries are recommended.

There are a lot of digital cameras out there, but here we have narrowed down some of the best online deals in quality compact and professional digital cameras.