Laptop buyer's guide

There's a dizzying array of laptops, notebooks and netbooks available today. Here's what you need to know to make a smart buy.

NOTEBOOKS and NETBOOKS

Laptop and notebook computers are largely the same although in some definitions notebook computers are more powerful than laptops. Netbooks are basically smaller, lighter and cheaper laptops that are designed to be ultraportable and rugged.

They typically have less processing power and memory than laptops and are designed for word processing, emailing and browsing the web rather than power and memory hungry functions such as gaming and editing and playing large media files.

PERFORMANCE

This is supplied by the laptop's processor or central processing unit (CPU), which carries out all the commands made by the laptop's hardware and software. A processor's speed is measured in gigahertz (Ghz). The higher the speed the more promptly the laptop will be able to respond to commands. Dual -core processors are faster than single-core processors.

Another important factor determining performance is memory. Also called random access memory (RAM), it stores frequently or currently used files for quick retrieval. Memory is measured in gigabytes.

If you're going to be playing videos or computer games it's a good idea to go for a laptop with a dual-core processor and at least 2GB of memory, and serious gamers probably want to opt for even more power. But if you're just after a laptop for basic word-processing and web-browsing, you can probably get away with less grunt.

HARD-DRIVE

This is where all your files and data are kept. If you're going to be saving music, videos, and photos it's a good idea to go for as much storage as possible. Storage is measured in gigabytes - go for at least 160GB. Your hard drive's speed is also important, the faster the hard-drive the better its performance.

Most hard-drives run at 5400 revolutions per minute or 7200rpm and these speeds should be adequate for most users. Serious gamers should go for the largest and fastest hard-drive they can afford.

Some laptops and netbooks come with solid state drives instead of hard-drives. Solid state drives have fewer moving parts than hard-drives and are usually more durable. They tend to have less capacity and consume less power but are more expensive.