Laptop Sizes

The size of screen you choose for your laptop will often dictate the overall size and weight of the machine. This may sound obvious but it pays to think how you are most likely to use your laptop. After all, opting for a 17-inch laptop when you plan to carry it around with you, will soon be a burden. Like wise, paying extra for an ultraportable that will never leave our desk is a false economy.

Screen sizes are changing all the time but the most common is the 15.4-inch widescreen panel, as it's a great compromise between portability and usability. Such machines usually weigh around 3kg. There are a variety of panel sizes starting at 7 inches to 10.2 inches for Netbooks and 10.6 inches up to 20.1 inches for fully-fledged laptops.

Screens dimensions

There are currently two different screen dimensions available - standard and widescreen.

16:10 aspect ratio
Better known as widescreen, they are squat but wider, so you can get more on them. Perfect for work but, more importantly, ideal for watching movies.

4:3 aspect ratio
This is a square display and can be found on cheaper, standard TFT machines, although many are now switching to widescreen.

Increasingly, we're starting to see the introduction of 16:9 aspect ratio screens that offer the same screen resolution as a normal widescreen TV, so you won't get that annoying black strip above and below the image shown. At the moment there are three sizes available - 13.1-inch, 16-inch and 18.4-inch. While pitched at the HD audience, you'll need to check the resolution the panel supports before you buy, as not all of them support Full HD (1080p).

DVD formats

Screen technology has developed in recent years. There are now a choice of technologies to take advantage of. The latest innovation in DVD formats is for high-definition DVD, which are discs that hold more data and are used to hold the latest movies in high-defi nition formats. Until recently there were two formats but that has now changed, with Blu-ray winning the format war.

Blu-ray: this is a high-density format that uses a blue laser to write more information on to a disc the same size as a CD. It’s a new technology that uses two lasers, unlike a DVD’s standard one laser, and allows for more information to be stored. Blu-ray can hold 25GB per layer, 50GB on a dual-layer disc. This extra storage space can be used for storing DVD movies in high-defi nition for better picture quality.

HD DVD: (High Density DVD) is next-generation DVD, so uses an enhanced version of current DVD technology, so discs and drives are cheaper, but a single layer disc can only hold 15GB and up to 30GB on a dual-layer disc. This format is no longer supported, so expect it to disappear by the end of 2008.

DVD Formats

There are a variety of DVD recording formats available, but as long as you have the right media for your drive, they work the same way. The most common are:

DVD-R: can record 4.5GB of data. It is a once-only format, so once fi nalised can be played by most DVD players, but cannot be written to again.

DVD-RW: can record up to 4.7GB, but with the advantage that you can add data to it at any time.

DVD+R: can record up to 4.7GB on a single-layered/singlesided disc. like DVD-R you can record only once.

DVD+RW: can record up to 4.7GB. Since it is rewritable, it can be overwritten several times.

DVD+R DL: DL stands for Dual Layer, which means you can use dual-layer recordable discs to store up to 8.5GB of data.

DVD-RAM: isn’t commonly used for home recording as it requires a special unit to play 4.7GB or 9.4GB recorded discs that are housed in a cartridge.