Digital cameras are the most convenient way to capture life's special moments. They come in all shapes, colours and sizes - from simple 'point and shoot' cameras, to professional-quality digital SLR models.

Taking pictures and instantly previewing them is simple, and because there are no developing costs, it's just a case of printing out your favourites.

You can get creative with loads of editing options, like red-eye reduction, artistic effects and colour balance. It's also easy to email pictures to friends, publish them on your blog or website, watch them as a high definition slideshow on your TV, or turn them into a greetings card or calendar.

Best of all, once you've taken a picture, the digital file will keep its colour and clarity forever - so your memories won't fade.

High Performance: digital SLR cameras use a Single Lens Reflex mechanism, like that used in an analogue SLR camera. They have protruding, interchangeable lenses that provide very powerful zoom magnification.

High or 'Telescopic' Zoom Compact: these cameras get up close to subjects using two different methods. Their optical, or mechanical, zoom magnifies a distant object while capturing quality and clarity. Their digital zoom enhances the size of captured images, but not quality or clarity. High zoom capability describes the number of times it magnifies an image, for example '8x optical zoom'.

Compact: a more basic, 'point and shoot' camera. Usually, it won't have a telescopic lens, but it may have a digital zoom to magnify the subject to a certain extent. Its manual mode will have automatic focus, and the resolution it can capture, measured in Megapixels, can be as high as a Digital SLR.

Resolution: the number of dots or pixels that make up the image; more pixels means more detail in the picture. Anything over 5MP (Megapixels) is good, while very high resolution 12MP cameras produce outstanding results. High resolution pictures have larger file sizes needing more memory, so use a lower resolution to send an image by email.

Memory: this varies from camera to camera, so it's usual to store photos on a separate memory card. Memory card formats vary - Sony uses memory sticks while Panasonic takes slightly smaller SD cards. Choose one that's compatible with your other devices, if you want to share cards. Cameras usually come with a USB cable for PC connection, so you won't need a card reader to start with.

Lens: the more expensive the camera, the better the lens. Only SLR cameras have interchangeable lenses, whereas 'point and shoot' camera lenses are either fixed, or mounted in a telescopic zoom assembly. For an idea of the camera's range, look at the 35mm equivalent rating: anything shorter than 50mm is wide-angle, while a lens longer than 50mm is telephoto - for close-ups.

Zoom: compact cameras with no telescopic lens can still magnify the image, but at the expense of picture quality. A telescopic lens can give 3x or 5x zoom magnification to capture distant subjects while keeping the picture quality. SLR cameras can offer zoom magnification of up to 60x.

LCD (Liquid Crystal Display) panel: this displays the subject you're shooting. The size and quality of LCD panels varies. A good LCD is often accompanied by a slideshow function that automatically displays pictures in sequence. Larger screens make filming easier and some are touch sensitive with controls located on the panel.

Battery: digital cameras can be heavy on battery use, especially if you use the flash, zoom or download often. Usually, cameras have a rechargeable lithium ion battery with a long charge-life, but it can be more convenient to choose a camera that takes regular AA batteries.

Video clip record: many digital cameras can capture short clips of film in AVI (Audio Video Interleave) format. This is easy to view on computer and share via email. The best video quality is 30fps VGA - a resolution of 640 x 480 - with sound. Video files use more memory than stills, and while you can record continuous video on some cameras, others allow only 30 seconds at a time, with or without sound.

Face recognition: the camera automatically 'recognises' faces and focuses on it, giving you clearer portraits.

Wireless connectivity: Wi-Fi lets you connect wirelessly to a computer or printer. Look for the Wi-Fi logo on the camera, and choose a printer and computer that are Wi-Fi enabled.

Waterproof: check specifications for allowed depth, without using additional protection. Water-resistant cameras are splash-proof, but won't survive submersion.

Scene modes: these optimise performance in specific situations. The 'Snow' setting sets the aperture and flash to suite bright white subject matter, while the 'Dusk' setting maximises exposure for more light. Each camera varies with the number and type of scenes offered.

Red-eye removal: prevents 'red-eye', often caused by the flash, by either modifying the actual flash or removing it from the photo via an in-camera feature.

Image stabiliser: compensates for shaky hands. Image stabilisers can be optical or, preferably, mechanical features.

PictBridge: connects the camera directly with a PictBridge-enabled printer, to print your photos without a computer.  

Software: digital cameras usually include a CD-ROM with photographic software, so you can manipulate or edit images. Check that it's compatible with your computer.

Camera Bag: SLR cameras are particularly delicate, and for these you'll find a huge variety of padded shoulder bags that will also take spare lenses and accessories.

Memory cards: to store lots of high Megapixel images, you'll need a high capacity card. Take care to choose a memory card that's compatible with your camera.

Imaging software: used on your computer, this can improve your photos. For more advanced image manipulation, try Adobe Photoshop or Apple Aperture.

Photo printer: Inkjet printers are good at printing photos onto glossy photo paper, while dedicated photo printers mean you don't need a computer.