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Chapter 4
Hardware and Software
Q1: What Do Business Professionals Need
to Know About Computer Hardware?
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Computer Data
•
Binary digits (bits)
― Used to represent data
― Bit is either 0 or 1
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Computer Data (cont’d)
•
Sizing Computer Data
― Bytes
― 8-bit chunk = 1 byte
•
Important storage capacity terminology
Name
Byte
Abbreviation
B
Number of Bytes
1 byte
Kilobyte
KB
1,024 bytes (210)
Megabyte
MB
1,048,576 bytes (220 bytes)
Gigabyte
GB
1,073,741,824 bytes (230 bytes)
Terabyte
TB
1,099,511,627,776 bytes (240 bytes)
Petabyte
PB
1,125,899,906,842,62 bytes (250 bytes)
Exabyte
EB
1,152,921,504,606,846,976 bytes (260 bytes)
Zettabyte
ZB
1,180,591,620,717,411,303,424 bytes (270 bytes)
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How Does a Computer Work?
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How Does a Computer Work? (cont’d)
(click here for more info)
CPU (Central Processing Unit)
Transfers program or data from disk to main memory
Moves instruction from main memory via data channel
or bus
Has small amount of fast memory called cache
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How Does a Computer Work? (cont’d)
Main
memory
contains
Operating
system
(OS)
•Program instructions
•Operating system instructions
•Program that controls computer’s
resources and blocks of data
•Provides services to application
programs and users
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Memory Swapping
Occurs when RAM is too small to hold all open
programs and data
CPU loads new program segments into unused
memory
• If none available, operating system swaps out existing
instructions, or data, to a disk and copy requested
program, or data, to freed space
• Swapping slows down your computer
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Why Should a Manager Care How a
Computer Works?
Main
memory
size
CPU
speed
•Too little means constant memory
swapping
•Need more memory for processing
many programs or large files
•Expressed in hertz (Hz):
 Electrical voltage that changes from low to
high and back again at regular intervals.
•Need more speed if handling large
spreadsheets or database files
•32-bit CPU  4 GB RAM
•64-bit CPU  almost unlimited RAM
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Why Should a Manager Care How a
Computer Works? (cont’d)
Cache and main memory are “volatile”
•Contents lost when power is cut off
Stores frequently used instructions
Large cache makes computer fast, but more expensive
Magnetic and optical disks are “nonvolatile”
―Saved contents survive after power is off
―Used for secondary storage
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Q2: What’s the Difference Between a Client
and a Server?
•
•
Client computers
used for word
processing,
spreadsheets,
database access
Servers provide
services to clients
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Server farm
•
•
•
•
Large collection of
coordinated servers
Amazon can process
110 order items per
second
Google Data sites
Inside a Google Data
Center (video)
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Q3: What Do Business Professionals Need
to Know About Software?
Operating systems
Run only on particular types of hardware
Must conform to instruction set of CPU
Windows works only on Intel instruction set CPUs
Application programs
Written for a particular operating system
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What a Manager Needs to Know about
Software
Four major operating systems
•
•
•
•
Windows (95% of business users)
Mac OS (graphic arts)
Unix (scientific & engineering applications)
Linux (open source community)
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What a Manager Needs to Know about
Software (cont’d)
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Own vs. License
License
Right to use specified
number of copies of a
program
Site License
Flat fee payment for
right to install software
product on all company
computers or computers
at specific site
Limits vendor’s
liability
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Cloud Computing and Virtualization
CLOUD computing
Guest Operating
Systems
IBM
Google docs
and
spreadsheets
Virtualization
Facebook
Windows
Linux
Oracle
Server virtualization makes
cloud computing feasible
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What Types Of Applications Exist and How
Do Organizations Obtain Them?
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What Is Firmware?
Computer software installed into hardware
devices
• Printers, print servers, communication devices
• Coded like other software
• Installed into read-only memory
• Can be changed and upgraded
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Q4: Why Are Thin Clients Preferred to Thick
Clients?
Thin client
•Requires nothing more than browser
•Does not require installation and administration of
client software
Thick client
•Has more code to run on it
•More features and functions
•More expense and administration
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Thin and Thick Clients
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Q5 Is Open Source Software a Viable
Alternative?
GNU general public license (GPL) agreement
•Standard for open source software
Successful open source projects
• OpenOffice (a Microsoft Office look-alike)
• Firefox (a browser)
• MySQL (a DBMS, see Chapter 5)
• Apache (a web server, see Chapter 8)
• Ubuntu (a Windows-like desktop operating system)
• Android (a mobile-device operating system)
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Why Do Programmers Volunteer Their
Services Open Source Projects?
Programming intense combination of art and logic
Freedom to choose projects work on
Exercise creativity working on interesting and fulfilling
projects
Exhibit one’s skill in order to get a job
Start a business selling services to support an open source
product
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How Does Open Source Work?
Machine code:
Source code is
compiled into
instructions
executed
directly by
a computer’s
CPU
Source
code:
Human
readable
computer
code
Software
Closed-source or
proprietary software.
Source code is not
available to users or
public. Only available
to trusted employees
and carefully vetted
contractors.
Open-source
software available to
users in source code
form.
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Source Code Sample
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So, Is Open Source Viable?
Depends on requirements and constraints of
situation. You will learn more about matching
requirements and programs in Chapter 10.
“Free” open source software requires support and
operational costs that could cost more than a
licensing fee.
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