What is Laptop? Part 2

Input/Output Interfaces

Input/output interfaces allow you to extend a laptop computer's functionalities by connecting external peripherals. Laptops generally have PC Card connectors (PCMCIA) that allow you to insert additional peripherals.

USB ports are available on all recent laptop computers but it is a good idea to verify if they are USB 1.0 ports, which offer a peak throughput of 12 Mbit/s, or USB 2.0 ports, which can have a peak throughput of up to 480 Mbit/s!

Having IEEE 1394 ports (with the commercial name of FireWire on Apple machines and i.LINK on IBM compatible machines) is a good idea for those users acquiring video from a DV digital video camera. FireWire ports allow throughputs on the order of 800 Mbit/s!

Some laptops come standard with multi-card readers that can read flash memories in the following different formats: Secure digital (SD Card), Multimedia Card (MMC), Memory stick (MS), SmartMedia (SM), Compact Flash (CF) or xD picture card. This type of reader can be extremely practical for those people who have MP3 players, digital cameras or personal desktop assistants (PDAs) because it facilitates the direct copying of files (e.g. music or digital photos) at a high bandwidth.

Audio and Video Input/Output

Every laptop computer has a screen and internal speakers but in some circumstances it is useful or even necessary to connect it to higher performance stereo or video systems (e.g. for a presentation or for a DVD projection).

Laptop computers come standard with a VGA connector, which allows you to connect them to an external monitor or a video projector. Sometimes laptops come equipped with a video output (called a TV output), i.e. a S-Video connector that allows you to connect the computer directly to a television.

With regard to audio I/O, all laptop computers come with standard headphone and microphone jacks as well as stereo speakers of varying quality. Having a S/PDIF output (digital audio output) can allow users to connect their laptop to a sound system that supports Dolby Digital 5.1 (e.g. for Home Cinema use).

Pointing Device / Keyboard

Laptop computers come standard with an integrated keyboard and pointing device. The pointing device is generally a touchpad, i.e. a flat touch-sensitive surface that allows you to move the cursor like a mouse. Some laptops come equipped with a trackpoint, i.e. a little touch-sensitive eraser-like tip (generally red) located in the middle of the keyboard that allows users to move the cursor with their fingers.

The keyboard and pointing device should be chosen according to their ergonomics. They should be tried out in order to determine if they are comfortable to use.

It should be noted that nothing prevents users from connecting a traditional mouse to a laptop computer for more comfort.
Mobility and Network Connectivity

In the communications world that we live in today, it is impossible to imagine a laptop computer without network functionalities. The terms nomadism and mobility are used to refer to individuals' capacity to have access to their information over the Internet, no matter where they are.

Most laptop computers come standard equipped with a 56K V90 modem that allows them to connect to the Internet over the telephone network (STN, switched telephone network).

The "10/100 Mbit Fast Ethernet" connector can be used to connect a laptop to a local area network (LAN) or to connect it to network equipment such as an ADSL modem, a router, a switch or even directly to another computer with a crossover network cable.

With the emergence of wireless networks and the increased number of public and private wireless network access points (called hot spots), the concept of nomadism is taking on a whole new meaning. Thus, some laptop computers now come standard with built-in or card WiFi adapters. WiFi technology allows computers equipped with specialised adapters (WiFi cards) to connect with each other over a range of several dozen or even hundreds of meters and possibly even to connect to the Internet thanks to a wireless router (WiFi terminal). There are several WiFi standards that use different transmission channels:

    WiFi 802.11a for a throughput of 54 Mb/s (30 Mb/s of real throughput)
    WiFi 802.11b for a throughput of 11 Mb/s (6 Mb/s of real throughput) with a range of up to 300 meters in an open environment
    WiFi 802.11g for a throughput of 54 Mb/s (30 Mb/s of real throughput) on a frequency band of 2.4 GHz.




Some laptops are equipped with Bluetooth technology, which is another wireless network technology. However, it is used primarily for wireless personal area network (WPAN), i.e. it is intended for small wireless devices such as mobile phones, PDAs, etc.

IrDa (infrared) technology allows users to connect small devices wirelessly to each other but, unlike BlueTooth technology, has distance limitations (several dozen centimetres facing each other) and reduced throughput.
Technical Characteristics

When you buy a laptop computers, in addition to choosing specific hardware elements you should carefully weigh the following characteristics:

    weight: a laptop computer is made to be transported, so it is important to choose the lightest one possible. Nevertheless, watch out for laptops that are light and have many external peripherals (CD-ROM/DVD-ROM drive, mouse, power supply, hubs, etc.)
    autonomy: Computer autonomy depends on how much energy a computer's components use as well as the battery's characteristics
        NiCad (Nickel / Cadmium): a rechargeable battery that is now obsolete because it suffered from the memory effect, i.e. a progressive decrease in the maximum charge when it is recharged when it is not completely "dead"
        NiMH (Nickel / Hybrid Metal): a rechargeable battery that works better than nickel-cadmium batteries
        Li-Ion (Lithium / Ion): a rechargeable battery used in most laptop computers. Li-Ion batteries perform well and are reasonably priced. Moreover, Li-Ion batteries do not suffer from the memory effect, which means that it is not necessary to run the battery dry before recharging it.
        Li-Polymer (Lithium / Polymer): a rechargeable battery that is equivalent to Li-Ion batteries in terms of performance but is much lighter because the battery electrolytes and microporous separator in Li-Ion batteries are replaced by a solid polymer that is much lighter. On the other hand, Li-Polymer batteries take longer to charge and their longevity is shorter


Generally, computer autonomy is expressed in the amount of time that a computer can remain in sleep mode and in use.

    Operating Temperature: Running certain parts of a laptop computer (particularly the processor) causes the temperature of the computer to increase and sometimes become bothersome (especially when the keyboard becomes too hot).


    Overheating can become a real danger that can worsen when the laptop is running with the screen down because this can prevent proper thermal dissipation.

    noise: In order to dissipate the heat caused by the running of different parts of the laptop (especially the processor), laptop computers are sometimes equipped with heat evacuation devices, such as fans, that can create loud, bothersome noises. This is also true for that motors that run the hard drives and CD/DVD drives/burners. Therefore, it is a good idea for buyers to enquire about the level of noise the computer makes when it runs.


Docking Station

Some laptops come with a docking station. This is the device that the laptop computer fits into in order to easily connect it with a keyboard, mouse, screen, etc.
Warranty

Buying a laptop computer is a big investment. Therefore it is necessary to protect yourself against the risks associated with computer failure by signing up for a warranty. The warranty is even more important for laptop computers because it is not possible to change parts (graphics card, sound card, etc.) like you can on desktop computers. Most offers automatically include at least one year but it might be a good idea to take a several year warranty extension in order to cover the maximum number of risks.


    Make sure you get information about the type of damages that are covered by the warranty. Batteries in particular are rarely covered.

Software Package

Laptop computers are almost systematically equipped with an operating system when you purchase them but some offers also include a whole package of useful software such as office tools, an encyclopaedia or even antivirus software. It is a good idea to keep this in mind when you are buying a laptop.
Protective Cover

If you are going to travel with your computer, it is necessary to have a computer bag in order to protect it when transporting it with all its accessories.

In addition, it is highly recommended that you invest in a security cable (Kensington ComboSaver), which allows you to attach the laptop to a fixed piece of furniture thanks to the standard notch that is found on almost all laptops on the market.