Chapter 3

COMPUTER & MOBILE DEVICES

So in this chapter, we will discuss further about computer :) Are you ready?? Okayyyyyyyyyyy

As all of us know, there various type of computer. In Chapter 1, I already mention some of them. Do you still remember? Nahh if not, go back to Chapter 1 and read it again :D

First of all, these are the types of computers :

a) Desktop and mobile computer

b) Server and terminals

c) Smartphones, digital cameras, e-book readers and portable media players

d) Game devices

e) Embedded computer

SERVER

In a technical sense, a server is an instance of a computer program that accepts and responds to requests made by another program, known as a client. Less formally, any device that runs server software could be considered a server as well. Servers are used to manage network resources. For example, a user may setup a server to control access to a network, send/receive e-mail, manage print jobs, or host a website.

How the server works?

First, browser breaks the url into three parts:

a) The protocol ("http")

b) The server name (www.unknown.com)

c) The file name (unknown.htm)

SUPERCOMPUTER

A supercomputer is a computer with a high level of computing performance compared to a general-purpose computer. Supercomputers play an important role in the field of computational science, and are used for a wide range of computationally intensive tasks in various fields, including quantum mechanics,weather forecasting,climate research,oil and gas exploration, molecular modeling (computing the structures and properties of chemical compounds, biological macromolecules, polymers, and crystals), and physical simulations (such as simulations of the early moments of the universe, airplane and spacecraft aerodynamics, the detonation of nuclear weapons, and nuclear fusion).

The differences between server and supercomputer :

SERVER	SUPERCOMPUTER
Serves bits and bytes of data that enter and leave the server	Regular hardware combined in enormous proportions
Web servers-processing requests from surfers and sending them back data	Contain so many processors
Web browsers - assemble that data to generate Web pages	Predict the weather, build airplanes, model the brain and simulate the way the planet works.
Server send files in a network.	Sequoia Blue Gene/Q supercomputer processing 504 billion events per second(2013) ≈1 million desktop computers.

*Table credit to Puan Juwita*

TERMINAL

A terminal is a computer, usually with limited processing power, that enables users to send data to and/or receive information from a server, or host computer.

a) ATM (Automated Teller Machine)

b) Self-service Kiosk

EMBEDDED COMPUTER

Embedded computer is a microcontroller or microprocessor based system devised for specific function. Embedded Computer performs specific functionality and used today in various applications. Embedded Computer may be a part of large system but it relies on its own processor. Cell phones, cameras, automotive systems etc. are some of the common examples of embedded computers.

Example of embedded computer in daily life :

PORT & CONNECTION

In computer hardware, a port serves as an interface between the computer and other computers or peripheral devices. In computer terms, a port generally refers to the female part of connection. Computer ports have many uses, to connect a monitor, webcam, speakers, or other peripheral devices. On the physical layer, a computer port is a specialized outlet on a piece of equipment to which a plug or cable connects. Electronically, the several conductors where the port and cable contacts connect, provide a method to transfer signals between devices.

Computer Port

Connector

HOW TO PROTECT YOUR HARDWARE

a) Surge Protector

A surge protector or surge suppressor or surge diverter is an appliance or device designed to protect electrical devices from voltage spikes. A surge protector attempts to limit the voltage supplied to an electric device by either blocking or shorting to ground any unwanted voltages above a safe threshold.

b) Uninterruptible Power Supply (UPS)

An electrical apparatus that provides emergency power to a load when the input power source or mains power fails. A UPS differs from an auxiliary or emergency power system or standby generator in that it will provide near-instantaneous protection from input power interruptions, by supplying energy stored in batteries, supercapacitors, or flywheels.