The last few years have seen an explosion of digital imaging technology. With camera prices dropping to phenomenally low levels, and the proliferation of cheap image editing and printing solutions, it is now easier than ever to capture and print photographs in the comfort of your own home.

So, you're thinking of taking the plunge and purchasing a digital camera, or perhaps upgrading an existing unit, but need some help wading through the photo and technical jargon? Then read on.

First things first: why do you want one?

The main decision you'll need to make before purchasing a digital camera is how you intend to use it. If, for example, you're an amateur photographer who's not interested in getting "arty" but just wants to take basic photos to e-mail to friends, then a lower-end camera will most likely suffice. If, however, you're keen to manipulate your photos and want to get into creative photography, a camera with manual options is going to better suit your needs.

For the purpose of this guide, we've described digital cameras as fitting into three main types: the lower-end or entry-level "point and shoot" device; the mid-range product, which can offer some manual capabilities; and the higher-end SLRs, which have a wider range of manual tools as well as optional extras.

Entry-level cameras are just that: good cameras for users who are keen to take small, medium-quality shots or the occasional family snap, or for users who don't know much about photography and want to get used to digital photography first. Entry-level cameras usually have a resolution ranging from 5Mp to 7Mp (1-megapixel equals 1 million pixels) with little or no manual options, and are priced around the $150-400 mark.

Mid-range cameras, the largest category of digital cameras, tend to offer more advanced features, such as manual shooting modes, larger optical zoom lenses and a resolution of 6Mp to 10Mp, so you can make larger prints and crop effectively. Expect to pay anything from $350 to $800.

Your last option is a digital SLR, the mack daddy of digital photography. Usually costing in excess of $1000 (and some models will set you back $6000 or more), they come with full manual functionality that far exceeds what is provided on even the most advanced compact camera. They give the user almost complete control by offering various extra features, such as increased zoom, interchangeable lenses and external flashes. They typically come with 8- or 10-megapixel sensors, although there are some monsters that offer 12 megapixels or more.

To help you figure out which one is best for you, we've put together some of the key features that you need to look at when purchasing a digital camera, as well as an overview of how digital cameras work.