Datasheet

or sitting out in the woods. The power supply’s other use is to charge and
recharge a battery that installs in a bay on the side or bottom of the laptop.
(You can also run many laptops using a special power adapter that plugs
into an automobile’s DC output — what used to be called the cigarette
lighter — or into a power source offered by some airlines. And some
current-model automobiles now offer a 110-volt AC outlet for use with
electronic devices.)
 Security lock slot: Most current laptops include a small attachment
point — connected to the internal metal or heavy-duty plastic shell of the
machine — for a locking cable. The good news about laptops is that they’re
easy to move around. The bad news is that bad people out there know this.
You can purchase a cable to loop around a pipe or other fixed object; a
special lock (keyed or combination) fits into the slot.
 Cooling vents: The flow of electrons through tiny wires within your laptop
is not perfectly free and easy. The friction of the electricity in the pipes
generates heat, and the faster the flow, the hotter the temperature. And of
course, today’s laptops are very fast. Heat within a laptop is exhausted to
the outside through the use of vents and one or more fans.
Cornering Input and Output
I was thinking about calling this section Ports Aplenty, which isn’t really a techni-
cal term, but nevertheless a pretty appropriate way to think about a laptop. Since
the machine’s essentially a sealed box meant to travel the globe, clever designers
have come up with all sorts of ways to allow you to attach external devices or
communicate through wires, networks, pulses of light, or radio waves.
Current I/O options
As technology marches along, ports may come and ports may go. For example,
the versatile USB port has taken over the role formerly played by a number of
older means of connection. Designers have ensured that nearly every piece of
external equipment, no matter how old, can find a way to communicate with
even the most modern machine.
First, consider the ports that are now common on current laptops:
 RGB (monitor) port: This is an output of the same image seen on the LCD
screen, converted to a signal that can display on a standard computer
monitor, or on a wall if you use an external video projector.
 S-video port: This port sends a relatively high-resolution video output to
modern TV sets that have a matching input. The picture quality is gener-
ally not quite as good as what you see on a computer monitor, but TVs are
usually larger than monitors.
Checking Out Basic Hardware — Cornering Input and Output 5
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