Much of the time, you will probably use your laptop computer without anything connected to it. However, you should still make sure it has all the input and output connectors that it needs to connect to the Internet or a local network, and to peripheral devices such as a printer, an external mouse, monitor, keyboard, and various USB devices.
A new laptop should include these connectors discussed in the sections that follow.
Many new computers use USB connectors as replacements for the older serial data port, printer port, and PS/2 keyboard and mouse sockets, so your laptop should have at least two or three USB sockets. The exact number of sockets is not particularly important because you can always use a USB hub to connect additional devices to the computer.
If you expect to use the computer with a video camera, audio production console, or other multimedia equipment, you also want an IEEE 1394 (FireWire) socket on your laptop. One is enough because the 1394 specification allows daisy-chain connections of multiple devices.
For a more detailed explanation of the USB and IEEE 1394 interface standards, see Chapter 14.
Your new laptop should have a high-speed Ethernet socket that can connect the computer to a local network or an Internet gateway, and a 56 Kbps modem port for connecting to the public telephone network.
A built-in Wi-Fi wireless networking transceiver is a standard feature of most new laptop computers. In most cases, the antenna associated with the Wi-Fi radio is built into the case, usually along one side of the monitor screen.
As wireless networking has evolved, several new versions have appeared, each with a different letter suffix. Many laptops use an Intel network adapter on a removable module that is compatible with all three Wi-Fi standards, 802.11a, 802.11b, and 802.11g. At a minimum, the Wi-Fi interface supplied with a new laptop should use the 802.11g standard, which is also compatible with 802.11b base stations.
Yet another Wi-Fi standard will probably be introduced sometime in 2007, with faster data transfer speed and greater signal range than the current versions. The working designation is 802.11n, but that might change when the standard is adopted by the IEEE and other industry groups. When 802.11n becomes available, it will be possible to remove the existing Wi-Fi module inside your laptop and replace it with a new one. In the meantime, several manufacturers offer "Pre-n" wireless routers and network adapters that use what the makers expect to be the new standard.
If you're not using a Wi-Fi connection when the computer is running on battery power, it should be possible to turn off the internal Wi-Fi transceiver to reduce the drain on the battery. Your new laptop should have either a dedicated switch or a Function key that can turn the Wi-Fi adapter on or off.
An internal Wi-Fi adapter inside your laptop is not absolutely essential. Separate Wi-Fi adapters are widely available on PC Cards.
See Chapter 44 for more information about configuring and using a Wi-Fi network.
Along with all those data connectors, a laptop computer usually has two audio sockets: a stereo output jack for headphones and an input plug for a microphone. This is probably adequate for listening to CDs, DVD movies, streaming radio from the Internet, and MP3 music files, but you want to use a separate USB or FireWire audio input device for serious recording.
PC Cards are credit card–sized modules that follow the PCMCIA specifications. PC Cards can contain network adapters, storage media, audio adapters, and dozens of other types of peripheral devices or interfaces for mobile computers. Before the USB interface was introduced, the PCMCIA socket was the main channel for connecting an add-on device to a laptop. PC cards are still handy for many applications, including TV tuners and GPS (global positioning system) receivers because they don't take up a lot of space outside the computer's case.
PC Cards come in three sizes: Type I is 3.3 mm thick, used mostly for memory cards; Type II is 5.0 mm thick, used for network interfaces and other I/O devices; and Type III is 10.5 mm thick, used for rotating disk drives (new Type III cards are extremely rare because flash media and thinner disk drives have replaced the older drives). A new laptop computer should have at least one PC Card socket, with enough clearance for a Type II card.
ExpressCards are the latest generation of PC Card technology. An ExpressCard is about half the width of a PC Card. Many laptops combine a PC Card socket and an Express Card socket in the same space.
For more about using PC Cards and Express Cards, see Chapter 24.
Some new laptops might still include PS/2 sockets for an external keyboard and mouse, but the latest generation of mice and keyboards come with USB plugs, so the PS/2 sockets are gradually disappearing. If your new computer doesn't include them, either use a USB mouse and keyboard, or find a couple of USB-to-PS/2 adapters.
An external video output connector isn't as important as it was in the days of laptops with 10-inch screens, but most new computers still include a VGA socket, a DVI socket or both. They're still useful for dual-display setups. If your monitor can accept only a digital input cable, make sure your new laptop has a DVI output connector.
Dual-display setups are discussed in more detail in Chapter 28.
A docking port is a single socket on the back or bottom of your laptop that connects to a separate connector panel where you can plug in the cables from an external keyboard, mouse, video display, and network access. If you use your laptop with those external peripherals in one location, but you also disconnect all those cables every time you travel with the computer, a docking port can save you some time and trouble.
The traditional multi-pin serial and parallel data ports that were the standard I/O ports on early personal computers are rapidly becoming obsolete. They're still common on desktop computers, but they're missing from many new laptops. Most of us won't miss them.
If you have to connect an old printer or some kind of serial device to your laptop, you need a serial or parallel adapter that plugs into a USB port or a PCMCIA socket.