William Miller - Instructor

Computers and Digital Basics Chapter 1

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1 ABACUS 4 th 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 ( ) 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 ( ) 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 ( ) 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 ( ) 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 ( ) 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 ( ) and John W. Mauchly ( ) 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 Keyboard No Video Display No 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 It features a simple, graphical interface, uses the 8-MHz, 32-bit Motorola CPU, and has a built-in 9-inch B/W screen.

1 Chapter 1: Computers and Digital Basics25 The Digital Revolution Digital 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

1 Chapter 1: Computers and Digital Basics26 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

1 Chapter 1: Computers and Digital Basics27 The Digital Revolution Computer Ownership in the USA

1 Chapter 1: Computers and Digital Basics28 The Digital Revolution What Caused the sudden upswing in computer ownership?  The second phase of the digital revolution materialized when the Internet was opened to public use – –Bulletin boards –Chat groups Blogs –Online social networks

1 Chapter 1: Computers and Digital Basics29 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:

1 Chapter 1: Computers and Digital Basics30 Convergence Technological convergence -process by which several technologies with distinct functionalities evolve to form a single product Convergence tends to offer enhanced functionality and convenience

1 Chapter 1: Computers and Digital Basics31 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

1 Chapter 1: Computers and Digital Basics32 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

1 Chapter 1: Computers and Digital Basics33 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

1 SECTION B Chapter 1: Computers and Digital Basics34 Digital Devices

1 Chapter 1: Computers and Digital Basics35 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

1 Chapter 1: Computers and Digital Basics36 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

1 Chapter 1: Computers and Digital Basics37 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

1 Chapter 1: Computers and Digital Basics38 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

1 Chapter 1: Computers and Digital Basics39 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)

1 Chapter 1: Computers and Digital Basics40 Personal Computers, Servers, Mainframes, and Supercomputers  A personal computer is a microprocessor-based computing device designed to meet the computing needs of an individual

1 Chapter 1: Computers and Digital Basics41 Personal Computers, Servers, Mainframes, and Supercomputers  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

1 Chapter 1: Computers and Digital Basics42 Personal Computers, Servers, Mainframes, and Supercomputers  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

1 Chapter 1: Computers and Digital Basics43 Personal Computers, Servers, Mainframes, and Supercomputers  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

1 Chapter 1: Computers and Digital Basics44 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, , 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, , 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 Basics45

1 Chapter 1: Computers and Digital Basics46 Microcontrollers  Microcontroller - a special-purpose microprocessor that is built into the machine it controls  Microcontrollers - can be embedded in all sorts of everyday devices

1 SECTION C Chapter 1: Computers and Digital Basics47 Digital Data Representation  Data Representation Basics  Representing Numbers, Text, and Pictures  Quantifying Bits and Bytes  Circuits and Chips

1 Chapter 1: Computers and Digital Basics48 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

1 Chapter 1: Computers and Digital Basics49 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

1 Chapter 1: Computers and Digital Basics50 Data Representation

1 Chapter 1: Computers and Digital Basics51 Quantifying Bits and Bytes

1 Chapter 1: Computers and Digital Basics52 Circuits and Chips  Integrated circuit (computer chip) - super-thin slice of semiconducting material packed with microscopic circuit elements

1 Chapter 1: Computers and Digital Basics53 Circuits and Chips  System board – The “main” circuit board of a digital device. This is where most of the electronics are typically.

1 SECTION D Chapter 1: Computers and Digital Basics54 Digital Processing  Programs and Instruction Sets  Processor Logic

1 Chapter 1: Computers and Digital Basics55 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.

1 Chapter 1: Computers and Digital Basics56 Programs and Instruction Sets

1 Chapter 1: Computers and Digital Basics57 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

1 Chapter 1: Computers and Digital Basics58 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 Chapter 1: Computers and Digital Basics59

1 Chapter 1: Computers and Digital Basics60 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

1 Chapter 1: Computers and Digital Basics61 Processor Logic

1 Chapter 1: Computers and Digital Basics62 Processor Logic

1 SECTION E Chapter 1: Computers and Digital Basics63 Password Security  Authentication Protocols  Password Hacks  Secure Passwords

1 Chapter 1: Computers and Digital Basics64 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

1 Chapter 1: Computers and Digital Basics65 Authentication Protocols

1 Chapter 1: Computers and Digital Basics66 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

1 Chapter 1: Computers and Digital Basics67 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 Chapter 1: Computers and Digital Basics68

1 Chapter 1: Computers and Digital Basics69 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

1 Chapter 1: Computers and Digital Basics70 Password Security  Password manager - stores user IDs with their corresponding passwords and automatically fills in login forms

Chapter 1 Complete Computers and Digital Basics