Expansion slots: Only a couple of netbooks have built-in expansion slots: Lenovo's IdeaPad S10 has an ExpressCard/34 slot, for example, and HP's Mini 2140 has an ExpressCard/54 slot. An ExpressCard slot is handy if you want to install a mobile data card for Internet access or a digital TV tuner, for example. However, USB devices exist that can be used for the same tasks. There's no need to buy a netbook with an ExpressCard slot unless you already have devices that require it.
Graphics: Netbooks don't have dedicated graphics processors; instead they have integrated graphics adapters, which use the CPU and the main system memory in order to perform many of their functions. This means that you can't use netbooks for sophisticated 3D graphics processing. As a result, netbooks can't run many games (unless they are quite old and don't require complex 3D graphics). The most common integrated graphics card in netbooks is the Intel Graphics Media Accelerator 950 (GMA 950). Some netbooks use the Intel GMA 500 integrated graphics card, which has more advanced video processing capabilities than the GMA 950. It is often used in netbooks that have a digital TV tuner.
Memory card slots: Like most regular sized notebooks, all netbooks have an SD card slot that can be used to quickly download images from a digital camera.
Networking: All netbooks have built-in wireless networking, as well as an Ethernet port. The wireless networking speed is usually up to 802.11g, but some netbooks support fast 802.11n Wi-Fi. The Ethernet speed is usually 10/100, but some high-end netbooks feature Gigabit Ethernet. If you will only be using a netbook to browse the Internet, then 802.11g and 10/100 Ethernet are fast enough. Opt for the faster networking speeds if you will be using the netbook to serve data to a media streamer, for example.
Optical drive: Due to their size, netbooks don't have space for an integrated optical drive. If you want to install programs off a CD or play DVD movies you will need an external DVD burner that plugs in to a USB port.
RAM: The first netbook that ASUS shipped had 512MB of RAM, but the majority of netbooks now have 1GB installed. They can usually be upgraded (sometimes with difficulty) to 2GB. They use DDR2 SDRAM SO-DIMM modules and some netbooks have two SO-DIMM slots while others have one slot and some built-in RAM.
Resolution: The first Eee PC, with its 7in screen, had a resolution of 800x480. Common resolutions today are 1024x576 (for netbooks with a 16:9 aspect ratio) and 1024x600 (for netbooks with a 16:10 aspect ratio). The resolution of 8.9in netbooks and 10.2in netbooks is the same — 1024x600. Netbooks with a 10.1in screen typically have a resolution of 1024x576. While it's a small difference, go for a model with the higher resolution if you can, as it will be more comfortable when browsing Web pages. Dell's Mini 10 and Sony's VAIO W series VPCW115XG (P/T/W) netbooks have a high definition screen with a desktop resolution of 1366x768, which is currently the highest resolution on the market for a netbook.
Screen size: The current crop of netbooks have 10.1in or 10.2in screens, but there is also an 11.6in model available from BenQ. The first netbook — the ASUS Eee PC 701 4G — had a 7in screen, and later models featured 8.9in screens.
Storage: Netbooks are available either with solid-state storage or conventional (spinning) hard drives. Solid-state drives have no moving parts, so they are less prone to losing data than spinning hard drives if you drop your netbook. However, the solid-state devices found in netbooks are not as fast as 5400rpm spinning hard drives. They also don't offer anywhere near as much storage as conventional hard drives. Other advantages of solid-state drives are that they are slightly lighter, they run cooler and they consume fractionally less electricity. Choose a solid-state drive if you want a netbook that will run almost silently and without vibration and you don't care about storage capacity. Choose a netbook with a conventional spinning hard drive if you want a large storage capacity (conventional drives in netbooks currently go up to 160GB). Some netbooks come with both a hard drive and a solid-state drive. In such a configuration the operating system is installed on the solid-state drive and the hard drive is used to store programs and data.
USB ports: Netbooks can have up to three USB 2.0 ports, although some models ship with only two. Toshiba (in its NB100 and NB200 netbooks) has the most advanced USB ports on the market: they can be used to charge devices, such as the iPhone or an MP3 player, even when the netbook is switched off.
Video out: Most netbooks come with a D-Sub (VGA) port which you can use to plug in an external monitor.
Warranty: Most netbooks on the market have a 12-month warranty; the only netbook with a 24-month warranty is Fujitsu's M2010.
Webcam: All netbooks ship with a built-in webcam that can be used for Skype and recording YouTube videos.
Weight: The weight of a netbook will be 1-1.6kg, depending on its screen size, battery type and other specifications.
On page 3: every netbook we've ever tested.