Computers

Designed by Terry WilhelmiDesigned by Terry Wilhelmi

Joseph Jacquard

Jacquard’sJacquard’s LoomLoom in 1810 in 1810 Emphasized three Emphasized three

computer concepts:computer concepts:

1. 1. InstructionsInstructions

- used punched cards- used punched cards

2. 2. Simple ProgramSimple Program

- series of instructions- series of instructions

3. 3. Automate jobAutomate job

- because of program- because of program

Charles Babbage

Father of ComputersFather of Computers Invented Invented Analytical Analytical EngineEngine in in

18321832 5 characteristics of 5 characteristics of modern modern

computercomputer InputInput device – punch device – punch cardscards ProcessorProcessor – mill – mill Control UnitControl Unit StorageStorage Facility – store Facility – store Output Output devicedevice

Ada Augusta

First Computer First Computer ProgrammerProgrammer

wrote programs for wrote programs for Analytical Analytical

EngineEngine Her notes on the Her notes on the

Analytical Engine Analytical Engine used in future used in future

development of development of computerscomputers

Gifted MathematicianGifted Mathematician

John MauchlyPresper Eckert

ENIAC ENIAC (Electronic (Electronic Numerical Numerical

Integrator & Integrator & Computer) Computer)

19461946 First electronic First electronic

computercomputer to go to go into operationinto operation

Developed to Developed to determine determine

artillery shell artillery shell trajectoriestrajectories

A moth got caught in the MARK II A moth got caught in the MARK II and and shorted shorted out a relayout a relay

Grace crawled in and removed it from inside Grace crawled in and removed it from inside the computerthe computer

Popularized the term “Popularized the term “bugbug” to signify any ” to signify any system failuresystem failure

The term “The term “debuggingdebugging” signifies solving a ” signifies solving a computer problemcomputer problem

John von Neumann

EDVAC - first electronic computer to use stored-programEDVAC - first electronic computer to use stored-program

“First Draft” – based onhis concepts, all computersprocess data by carrying outfour specific activities:

Input dataStore dataProcess dataOutput data/results

This initiated the moderncomputer era.

Computer An electronic device that does computations and An electronic device that does computations and

makes logical decisions according to makes logical decisions according to instructions and data that have been instructions and data that have been

given to given to it.it. Accomplished by accepting input, processing Accomplished by accepting input, processing it it

according to instructions, storing the data, according to instructions, storing the data, and and producing the requested results (output).producing the requested results (output).

Three basic functions:Three basic functions: Arithmetic operationsArithmetic operations – add, subtract, multiply, divide – add, subtract, multiply, divide Logical comparisonsLogical comparisons of values - >, <, =, <>, >=, <= of values - >, <, =, <>, >=, <= Storage and retrievalStorage and retrieval operations operations

Advantages Limitations

SpeedSpeed Billions of operations Billions of operations

per secondper second AccuracyAccuracy

Durability and Durability and reliability of its reliability of its circuitrycircuitry

Storage CapabilitiesStorage Capabilities Stores large amounts Stores large amounts

of data that can be of data that can be retrieved quicklyretrieved quickly

Unable to think and Unable to think and build on past build on past experiencesexperiences

Not suited for tasks Not suited for tasks that involve complex that involve complex decision makingdecision making

Internal Representation of Data

InputInput Data that is put into the computer for Data that is put into the computer for

processingprocessing DataData

The raw material to be processed by a computerThe raw material to be processed by a computer InformationInformation

Data that is organized, meaningful, & usefulData that is organized, meaningful, & useful To be useful, information must be:To be useful, information must be:

Complete, accurate, relevant, Complete, accurate, relevant, && timely timely

Pioneers

George BooleGeorge Boole 1800’s1800’s Boolean mathematicsBoolean mathematics Human reason could be reduced to Human reason could be reduced to yes/no yes/no

questionsquestions

George ShannonGeorge Shannon 19371937 Used Boolean logic to wire electrical switchingUsed Boolean logic to wire electrical switching

Binary Number System

Electrical circuits/switches have one of two states Electrical circuits/switches have one of two states – on or off (light switch)– on or off (light switch)

Binary SystemBinary System (Base of 2) – uses two numbers to (Base of 2) – uses two numbers to represent the states: represent the states: 11 for for ONON and and 00 for for

OFFOFF

BitBit ( (BiBinary Diginary Digitt) – each ) – each 11 or or 00

ByteByte – an – an 8-bit8-bit unit that represents unit that represents

one characterone character

Decimal to Binary

There can be as many 0’s and 1’s as required within eight There can be as many 0’s and 1’s as required within eight places to represent a particular characterplaces to represent a particular character

ASCII Code

American Standard Code American Standard Code for Information for Information InterchangeInterchange

Small computers use Small computers use ASCII code to convert ASCII code to convert characters into the characters into the machine language of 1’s machine language of 1’s and 0’s.and 0’s.

Conversion is handled by Conversion is handled by the computer system’s the computer system’s input and output devicesinput and output devices

Crimes Using Computers

Computer CrimeComputer Crime Theft of ServicesTheft of Services Theft of PropertyTheft of Property Financial CrimesFinancial Crimes SoftwareSoftware

Computer Crime A criminal act that is accomplished through A criminal act that is accomplished through the the

use of a computeruse of a computer A criminal act that poses a greater threat to a A criminal act that poses a greater threat to a

computer user than it would to a computer user than it would to a non-computer usernon-computer user

Kinds of activity:Kinds of activity: Perpetrate acts of deceit, theft, or concealment Perpetrate acts of deceit, theft, or concealment

to provide financial, business-related, to provide financial, business-related, property, or service advantagesproperty, or service advantages

Threats to computer itself – sabotage, theftThreats to computer itself – sabotage, theft

Theft of Services

Using a company’s computer after working Using a company’s computer after working hourshours

Obtaining inside information on a Obtaining inside information on a business/corporationbusiness/corporation

Making unauthorized changes to data Making unauthorized changes to data (grades)(grades)

Theft of valuable computer time and the Theft of valuable computer time and the data stored on the systemdata stored on the system

Theft of Property

Computer itselfComputer itself Computer parts for assembly laterComputer parts for assembly later Stealing merchandise from a company Stealing merchandise from a company

whose orders are processed by whose orders are processed by computerscomputers

SoftwareSoftware Illegally copying software, music, etc.Illegally copying software, music, etc.

Financial Crimes

Creating illegal checks by an employeeCreating illegal checks by an employee ““Round-off fraud” – an employee collects Round-off fraud” – an employee collects

the fractions of cents in the fractions of cents in customers’ customers’ accounts due to accounts due to applicable interest rate applicable interest rate allocationsallocations

Software Software piracySoftware piracy – stealing commercial – stealing commercial

software either outright or illegally software either outright or illegally copying copying it for personal use or for resaleit for personal use or for resale

Commercial softwareCommercial software – software ordinarily – software ordinarily purchased at a store, via Internet or mailpurchased at a store, via Internet or mail CopyrightedCopyrighted – we purchase right to use software – we purchase right to use software ConstitutionConstitution in in 17901790 – protects rights of authors – protects rights of authors US Copyright OfficeUS Copyright Office & & courtscourts in in 19641964 – –

established that computer programs are the established that computer programs are the “writing of an author”“writing of an author”

Laws

Copyright Act of 1976Copyright Act of 1976 ““It is illegal to make unauthorized copies of It is illegal to make unauthorized copies of

a copyrighted computer program.” a copyrighted computer program.”

Software Piracy and Counterfeiting Software Piracy and Counterfeiting Amendment of 1983Amendment of 1983

Added to the Copyright Act of 1976Added to the Copyright Act of 1976 Commercially copying and selling pirated Commercially copying and selling pirated

software is a software is a felonyfelony

Security Issues in Workplace

Safeguards designed to protect a computer system and data Safeguards designed to protect a computer system and data from deliberate or accidental damage or access by from deliberate or accidental damage or access by unauthorized persons.unauthorized persons.

Dishonest employees sell information to Dishonest employees sell information to competitorcompetitor

Employee carelessness/poor training causes damage to Employee carelessness/poor training causes damage to computer hardware, software, and datacomputer hardware, software, and data

Infecting computer systems with destructive virusesInfecting computer systems with destructive viruses SabotageSabotage

Privacy and Confidentiality of Information

PrivacyPrivacy – keeping personal information – keeping personal information personal; protecting it from improper usepersonal; protecting it from improper use

Computer Fraud and Abuse Act (1986)Computer Fraud and Abuse Act (1986) Obtaining records from financial institutionsObtaining records from financial institutions

Electronic Communication Privacy Act (1986)Electronic Communication Privacy Act (1986) Prohibits the interception of data communicationsProhibits the interception of data communications

Computer Matching and Privacy Protection Act (1988)Computer Matching and Privacy Protection Act (1988) Regulates use of data for eligibility of federal Regulates use of data for eligibility of federal

benefitsbenefits

Ethics A set of moral principles or values that are A set of moral principles or values that are

designed to guide human conductdesigned to guide human conduct Dealing with what is good and bad, ethics Dealing with what is good and bad, ethics

represents a pattern of personal conduct represents a pattern of personal conduct that is that is acceptable to societyacceptable to society

Computer ethicsComputer ethics The standard of moral conduct in computer useThe standard of moral conduct in computer use A way in which the “spirit” of laws can be A way in which the “spirit” of laws can be

carried to other computer-related carried to other computer-related activitiesactivities

Individual license - Individual license - use only one program use only one program on one computer at a timeon one computer at a time

Ethical Responsibilities Ethical Responsibilities of a Programmerof a Programmer

Increased use of computers to control potentially dangerous devices such as aircraft, nuclear reactors, or sensitive medical equipment places a strong ethical burden on the programmer to insure, as best as he or she can, the reliability of the computer software.

EthicsEthicsA set of moral principles or values that A set of moral principles or values that are designed to guide human conductare designed to guide human conduct

Control Frustrations