William Miller - Instructor. Computers and Digital Basics Chapter 1.

William Miller - Instructor

COSC 1401

Computer Applications


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Computers and Digital Basics

Chapter 1

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1 ABACUS

4th Century B.C.

The abacus, a simple counting aid, may have been invented in Babylonia (now Iraq) in the fourth century B.C.

This device allows users to make computations using a system of sliding beads arranged on a rack.

1 BLAISE PASCAL

(1623 - 1662)

In 1642, the French mathematician and philosopher Blaise Pascal invented a calculating device that would come to be called the "Adding Machine".

1 BLAISE PASCAL

(1623 - 1662)

Originally called a "numerical wheel calculator" or the "Pascaline", Pascal's invention utilized a train of 8 moveable dials or cogs to add sums of up to 8 figures long. As one dial turned 10 notches - or a complete revolution - it mechanically turned the next dial.

Pascal's mechanical Adding Machine automated the process of calculation. Although slow by modern standards, this machine did provide a fair degree of accuracy and speed.

1 CHARLES BABBAGE

(1791 - 1871)

Born in 1791, Charles Babbage was an English mathematician and professor.

In 1822, he persuaded the British government to finance his design to build a machine that would calculate tables for logarithms.

With Charles Babbage's creation of the "Analytical Engine", (1833) computers took the form of a general purpose machine.

1 HOWARD AIKEN

(1900 - 1973)

Aiken thought he could create a modern and functioning model of Babbage's Analytical Engine.

He succeeded in securing a grant of 1 million dollars for his proposed Automatic Sequence Calculator; the Mark I for short. From IBM.

In 1944, the Mark I was "switched" on. Aiken's colossal machine spanned 51 feet in length and 8 feet in height. 500 meters of wiring were required to connect each component.

1 HOWARD AIKEN

(1900 - 1973)

The Mark I did transform Babbage's dream into reality and did succeed in putting IBM's name on the forefront of the burgeoning computer industry. From 1944 on, modern computers would forever be associated with digital intelligence.

1 ENIAC

1946

Electronic Numerical Integrator And Computer

Under the leadership of J. Presper Eckert (1919 - 1995) and John W. Mauchly (1907 - 1980) the team produced a machine that computed at speeds 1,000 times faster than the Mark I was capable of only 2 years earlier.

Using 18,00-19,000 vacuum tubes, 70,000 resistors and 5 million soldered joints this massive instrument required the output of a small power station to operate it.

1 ENIAC

1946

It could do nuclear physics calculations (in two hours) which it would have taken 100 engineers a year to do by hand.

The system's program could be changed by rewiring a panel.

1 ENIAC

1946

1 TRANSISTOR

1948

In the laboratories of Bell Telephone, John Bardeen, Walter Brattain and William Shockley discovered the "transfer resistor"; later labelled the transistor.

Advantages:

increased reliability

1/13 size of vacuum tubes

consumed 1/20 of the electricity of vacuum tubes

were a fraction of the cost

1 TRANSISTOR

1948

This tiny device had a huge impact on and extensive implications for modern computers. In 1956, the transistor won its creators the Noble Peace Prize for their invention.

1 ALTAIR

1975

The invention of the transistor made computers smaller, cheaper and more reliable. Therefore, the stage was set for the entrance of the computer into the domestic realm. In 1975, the age of personal computers commenced. Under the leadership of Ed Roberts the Micro Instrumentation and Telemetry Company (MITS) wanted to design a computer 'kit' for the home hobbyist.

1 ALTAIR

1975

Based on the Intel 8080 processor, capable of controlling 64 kilobyes of memory, the MITS Altair - as the invention was later called - was debuted on the cover of the January edition of Popular Electronics magazine.Presenting the Altair as an unassembled kit kept costs to a minimum. Therefore, the company was able to offer this model for only $395. Supply could not keep up with demand.

1 ALTAIR

1975

ALTAIR FACTS:No KeyboardNo Video DisplayNo Storage Device

1 IBM (PC)

1981

On August 12, 1981 IBM announced its own personal computer. Using the 16 bit Intel 8088 microprocessor, allowed for increased speed and huge amounts of memory. Unlike the Altair that was sold as unassembled computer kits, IBM sold its "ready-made" machine through retailers and by qualified salespeople.

1 IBM (PC)

1981

To satisfy consumer appetites and to increase usability, IBM gave prototype IBM PCs to a number of major software companies.For the first time, small companies and individuals who never would have imagined owning a "personal" computer were now opened to the computer world.

1 MACINTOSH

(1984)

IBM's major competitor was a company lead by Steve Wozniak and Steve Jobs and Ronald Wayne; the Apple Computer Inc. The "Lisa" was the result of their competitive thrust. This system differed from its predecessors in its use of a "mouse" - then a quite foreign computer instrument - in lieu of manually typing commands. However, the outrageous price of the Lisa kept it out of reach for many computer buyers.

*Ronald Wayne gave up his share of the new company for a total of $2,300.

1 MACINTOSH

(1984)

Apple's brainchild was the Macintosh. Like the Lisa, the Macintosh too would make use of a graphical user interface. Introduced in January 1984 it was an immediate success. The GUI (Graphical User Interface) made the system easy to use.

1 MACINTOSH

(1984)

The Apple Macintosh debuts in 1984. It features a simple, graphical interface, uses the 8-MHz, 32-bit Motorola 68000 CPU, and has a built-in 9-inch B/W screen.

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Chapter 1: Computers and Digital Basics 25

The Digital RevolutionDigital revolution - an ongoing process of social, political, and

economic change brought about by digital technology, such as computers and the Internet

Revolves around a constellation of technologies, including digital electronics, computers, communications networks, the Web, and digitization

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The Digital Revolution Digital electronics use electronic circuits to represent data Digital electronic devices include computers, portable media

players such as iPods, digital cameras and camcorders, cell phones, radios and televisions, GPSs, DVD and CD players, e-book readers, digital voice recorders, and handheld gaming consoles

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The Digital Revolution

Computer Ownership in the USA

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The Digital RevolutionWhat Caused the sudden upswing in computer ownership? The second phase of the digital revolution materialized when

the Internet was opened to public use– E-mail– Bulletin boards– Chat groups

• Blogs– Online social

networks

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The Digital Revolution

A computer network is a group of computers linked by wired or wireless technology to share data and resources

The Web is a collection of linked documents, graphics, and sounds that can be accessed over the Internet

Cyberspace is a term that refers to entities that exist largely within computer networks

Digitization is the process of converting text, numbers, sound, photos, and video into data that can be processed by digital devices

Some Terms:

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ConvergenceTechnological convergence -process by

which several technologies with distinct functionalities evolve to form a single product

Convergence tends to offer enhanced functionality and convenience

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Digital Society Digital technologies and communications networks make it

easy to cross cultural and geographic boundaries Anonymous Internet sites, such as Freenet, and anonymizer

tools that cloak a person’s identity, even make it possible to exercise freedom of speech in situations where reprisals might repress it

Citizens of free societies have an expectation of privacy Intellectual property refers to the ownership of certain types

of information, ideas, or representations

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Digital Society Digital technology is an important factor in global and

national economies, in addition to affecting the economic status of individuals

Globalization - the worldwide economic interdependence of countries that occurs as cross-border commerce increases and as money flows more freely among countries

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Digital Society Individuals are affected by the digital divide, a term that

refers to the gap between people who have access to technology and those who do not

Digital technology permeates the very core of modern life

1SECTION B


Digital Devices

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Computer Basics A computer is a multipurpose device that accepts input,

processes data, stores data, and produces output, all according to a series of stored instructions

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Computer Basics Input - whatever is typed, submitted, or

transmitted to a computer system Output the result produced by a computer Data - refers to the symbols that represent facts,

objects, and ideas Computers manipulate data in many ways, and

this manipulation is called processing– Central Processing Unit (CPU)– Microprocessor

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Computer Basics Memory - area of a computer that temporarily holds data

waiting to be processed, stored, or output Storage - area where data can be left on a permanent basis

when it is not immediately needed for processing File - named collection of data that exists on a storage

medium Computer program - series of instructions that tells a

computer how to carry out processing tasks.– Software

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Computer Basics Stored program - a series of instructions for a computing

task can be loaded into a computer’s memory– Allows you to switch between tasks– Distinguishes a computer from other simpler devices

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Computer Basics Application software - set of computer programs that helps

a person carry out a task System software - helps the computer system monitor itself

in order to function efficiently– Operating system (OS)

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Personal Computers, Servers, Mainframes, and Supercomputers

A personal computer is a microprocessor-based computing device designed to meet the computing needs of an individual

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The term workstation has two meanings:– An ordinary personal computer that is connected to a

network– A powerful desktop computer used for high-performance

tasks

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Videogame console: not generally referred to as personal computers because of their history as dedicated game devices.– Nintendo’s Wii– Sony’s PlayStation– Microsoft’s Xbox

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Server - serves other computers on a network (such as the Internet or a home network) by supplying them with data.

Mainframe computer (or simply a mainframe) is a large and expensive computer capable of simultaneously processing data for hundreds or thousands of users

Supercomputer - at the time of construction, one of the fastest computers in the world

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PDAs, Smart Phones, and Portable Media Players

PDA (personal digital assistant) - pocket-sized digital appointment book with a small qwerty keyboard or a touch-sensitive screen, designed to run on batteries and be used while holding it.– Palm Pilot

Handheld computer - essentially a PDA enhanced with features such as removable storage, e-mail, Web access, voice communications, built-in camera, and GPS– Apple iPhone, Palm Treo, RIM Blackberry

1 PDAs, Smart Phones, and Portable Media Players

Smart phone - in addition to voice communication, includes features such as full qwerty keypad, text messaging, e-mail, Web access, removable storage, camera, FM radio, digital music player, and software options for games, financial management, personal organizer, GPS, and maps

Portable media players - device that their main strength is playing music, showing videos, and storing photos such as iPods.

______ ________ ___ ______ _____Chapter 1: Computers and Digital Basics 4545

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Microcontrollers Microcontroller - a special-purpose microprocessor that is

built into the machine it controls Microcontrollers - can be embedded in all sorts of everyday

devices

1SECTION C


Digital Data Representation Data Representation Basics Representing Numbers, Text, and Pictures Quantifying Bits and Bytes Circuits and Chips

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Data Representation Data representation refers to the form in which data is

stored, processed, and transmitted Digital devices work with distinct and separate data Analog devices work with continuous data

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Representing Numbers, Text, and Pictures

Numeric data– Binary number system

Character data – Composed of letters, symbols and numerals that are not involved in arithmetic operations. Digital devices employ several types of coeds that represent character data: – ASCII, Extended ASCII, EBCDIC,

and Unicode Digitizing - process of converting

analog data into digital format

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Data Representation

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Quantifying Bits and Bytes

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Circuits and Chips Integrated circuit (computer chip) - super-thin slice of

semiconducting material packed with microscopic circuit elements

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Circuits and Chips System board – The

“main” circuit board of a digital device. This is where most of the electronics are typically.

1SECTION D


Digital Processing Programs and Instruction Sets Processor Logic

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Programs and Instruction Sets Computer programmers - create programs that control

digital devices. These programs are usually written in a high-level programming language

Source code - The human-readable version of a program created in a high-level language by a programmer.

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Programs and Instruction Sets

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Programs and Instruction Sets Instruction set - a collection of preprogrammed activities a

microprocessor is hardwired to perform Each instruction has a corresponding sequence of 0s and 1s The end product is called machine code

– 1s and 0s

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Programs and Instruction Sets Op code (short for operation code) - command word for an

operation such as add, compare, or jump Operand - specifies the data, or the address of the data, for

the operation In the following instruction, the op code means add and the

operand is 1, so the instruction means Add 1

1 Programs and Instruction Sets


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Processor Logic ALU (arithmetic logic unit) - the part of the microprocessor

that performs arithmetic operations Registers - what the ALU uses to hold the data that is being

processed Control unit - The microprocessor’s control unit fetches

each instruction, just as you get each ingredient out of a cupboard or the refrigerator

Instruction cycle - refers to the process in which a computer executes a single instruction

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Processor Logic

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Processor Logic

1SECTION E


Password Security Authentication Protocols Password Hacks Secure Passwords

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Authentication Protocols Authentication Protocol - method that confirms a person’s

identity using something the person knows, something the person possesses, or something the person is– A person can also be identified by biometrics, such as a

fingerprint, facial features (photo), or retinal pattern– A user ID is a series of characters—letters and possibly

numbers or special symbols—that becomes a person’s unique identifier

– A password is a series of characters that verifies a user ID and guarantees that you are the person you claim to be

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Authentication Protocols

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Password Hacks Identity theft - When someone gains unauthorized access

to your personal data and uses it illegally Hackers employ a wide range of ways to steal passwords Dictionary attack - helps hackers guess your password by

stepping through a dictionary containing thousands of the most commonly used passwords

Brute force attack - uses password-cracking software, but its range is much more extensive than the dictionary attack

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Password Hacks Sniffing - If hackers can’t guess a password, they can use

another technique called sniffing, which intercepts information sent out over computer networks

Phishing - attempting to acquire sensitive information such as usernames, passwords and credit card details by masquerading as a trustworthy entity in an electronic communication.

Keylogger - software that secretly records a user’s keystrokes and sends the information to a hacker

1 Password Security


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Password Security Strive to select a unique user ID that you can use for more

than one site Maintain two or three tiers of passwords

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Password Security Password manager - stores user IDs with their

corresponding passwords and automatically fills in login forms

Chapter 1 CompleteComputers and Digital Basics

William Miller - Instructor. Computers and Digital Basics Chapter 1.

Documents

cost slide

mark i

modern computers

general purpose machine

aikens colossal machine

modern standards

howard aiken

size of vacuum tubes