The netbook is one of the most interesting categories on the market. These small laptops can do most of the jobs of their big brothers while costing under US$500. For some people, such as students, a netbook can be a primary computer. For a business user, it might be a second PC for use when traveling or commuting. Here are five tips to help pick the right one for your needs.

1. Choose your operating system wisely

Depending on the vendor, netbooks are usually offered with Linux variants, Windows XP or Windows Vista. For the most part, I'd ignore the Linux devices. True, they're cheaper (since there's no need to pay for a Windows license), and they're usually loaded with open-source software, so things like an office suite, instant-messaging client and other applications are available from the get-go. But most users will struggle to add new applications to these machines, and the latest and greatest hardware peripherals usually aren't supported.

I'd avoid Vista as well. For the most part, netbook hardware is too slimmed-down to run Vista well. Most users will do best sticking with good old Windows XP. Microsoft recently allowed OEMs to continue to offer XP on netbooks, and that's a good thing. XP brings the breadth of Windows applications and devices, and it's been around long enough to work well on this class of device. The downside: Windows XP netbooks usually come with XP Home or XP Pro, but that's something that's easily fixed.

2. Avoid the SSD

It's cool to have a solid-state drive instead of magnetic media, but I'd avoid SSDs for now. The price/performance benefit isn't there just yet, and that's especially true for machines that cost under US$500. At that price, you can expect to max out at perhaps 16GB or 20GB for an SSD, but at 120GB to 160GB for a hard disk drive. Even if your storage needs are modest, you'll want the larger drive. And if you're looking at the netbook as a primary device, it's a no-brainer.

3. Screen size matters

You can find netbooks with 7- or 8-in. screens, but I'd recommend a 10-in. screen. You need a resolution of about 1,024-by-600 to run Windows well, and that just renders too small for most folks on anything tinier than a 10-in. display.