Datasheet

 USB port: This high-speed, highly adaptable port (some laptops offer two
or even three of them) can be used for almost any type of device, from
printers to external keyboards to various forms of add-on storage. A USB
port provides both data and electrical power to attached devices, although
some high-demand devices may require their own AC or battery power
source. And if you need to plug in more devices than you have USB ports,
you can add a
hub that splits the signal and provides more connecting
points.
 eSATA port: Designers promise to extend the high-speed internal Serial
ATA bus from inside the laptop to work with devices outside. Hence the
acronym that adds
e for external. The specification, in its eSATA 3.0 Gbps
version, delivers (wait for it) . . . 3.0 Gbps of data transfer, which is very
fast—speedier than USB 2.0. In theory, an external hard drive or DVD drive
connected this way operates no slower than an internal device. The port
also delivers electrical power.
 Ethernet port: This connects a network interface within the laptop and a
wired network of other computers or devices. It can also directly connect
to a high-speed broadband modem, such as one that uses a cable televi-
sion, DSL, or fiber-optics network. The connector, which looks like an over-
sized telephone jack, is technically called an
RJ-45.
 Modem port: If the laptop has a built-in telephone modem, this port accepts
a cable (with an RJ-11 connector) that attaches to the phone network.
 Headphone/speakers jack: The tiny connector can provide stereo audio to
a set of headphones, send a signal to a set of external speakers, or connect
to the sound circuitry of a television set, video projector, or stereo ampli-
fier and speaker system. You can purchase adapters that allow just about
any audio device to plug into and use the signal from this jack.
 Microphone jack: Attaching a microphone to this jack permits recording of
voice or live music, or provides an input to speech-recognition software for
dictation or verbal commands to the computer. The jack isn’t intended for
use with amplified line signals, such as those that come from a stereo
system or an iPod.
 Line-in jack: This connection, common only on laptops marketed as multi-
media devices, allows connection of an external source of audio such as
the output of a receiver, a VCR, or a stereo system. If your machine does
not have a line-in jack and you want to record amplified sound, your best
bet is to purchase a USB adapter that adds an external sound card and
additional jacks.
 iLink/FireWire port: You can call it iLink or you can call it FireWire or you
can refer to it by its technical specification, IEEE 1394. Just call it fast. This
is a competitive technology to the USB port that Sony (under the iLink
designation) has adopted for audiovisual devices including digital video
6 Part 1: The Laptop Computer
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