History of Computers

This chapter is a brief summary of the history of Computers. It is supplemented by the two PBS documentaries video tapes "Inventing the Future" And "The Paperback Computer". The chapter highlights some of the advances to look for in the documentaries.
In particular, when viewing the movies you should look for two things:

• The progression in hardware representation of a bit of data:
  1. Vacuum Tubes (1950s) - one bit on the size of a thumb;
  2. Transistors (1950s and 1960s) - one bit on the size of a fingernail;
  3. Integrated Circuits (1960s and 70s) - thousands of bits on the size of a hand
  4. Silicon computer chips (1970s and on) - millions of bits on the size of a finger nail.
  
  
• The progression of the ease of use of computers:
  1. Almost impossible to use except by very patient geniuses (1950s);
  2. Programmable by highly trained people only (1960s and 1970s);
  3. Useable by just about anyone (1980s and on).

to see how computers got smaller, cheaper, and easier to use.

First Computers

Eniac Computer

The first substantial computer was the giant ENIAC machine by John W. Mauchly and J. Presper Eckert at the University of Pennsylvania. ENIAC (Electrical Numerical Integrator and Calculator) used a word of 10 decimal digits instead of binary ones like previous automated calculators/computers. ENIAC was also the first machine to use more than 2,000 vacuum tubes, using nearly 18,000 vacuum tubes. Storage of all those vacuum tubes and the machinery required to keep the cool took up over 167 square meters (1800 square feet) of floor space. Nonetheless, it had punched-card input and output and arithmetically had 1 multiplier, 1 divider-square rooter, and 20 adders employing decimal "ring counters," which served as adders and also as quick-access (0.0002 seconds) read-write register storage.
The executable instructions composing a program were embodied in the separate units of ENIAC, which were plugged together to form a route through the machine for the flow of computations. These connections had to be redone for each different problem, together with presetting function tables and switches. This "wire-your-own" instruction technique was inconvenient, and only with some license could ENIAC be considered programmable; it was, however, efficient in handling the particular programs for which it had been designed. ENIAC is generally acknowledged to be the first successful high-speed electronic digital computer (EDC) and was productively used from 1946 to 1955. A controversy developed in 1971, however, over the patentability of ENIAC's basic digital concepts, the claim being made that another U.S. physicist, John V. Atanasoff, had already used the same ideas in a simpler vacuum-tube device he built in the 1930s while at Iowa State College. In 1973, the court found in favor of the company using Atanasoff claim and Atanasoff received the acclaim he rightly deserved.

Progression of Hardware

In the 1950's two devices would be invented that would improve the computer field and set in motion the beginning of the computer revolution. The first of these two devices was the transistor. Invented in 1947 by William Shockley, John Bardeen, and Walter Brattain of Bell Labs, the transistor was fated to oust the days of vacuum tubes in computers, radios, and other electronics.

Vaccum Tubes

The vacuum tube, used up to this time in almost all the computers and calculating machines, had been invented by American physicist Lee De Forest in 1906. The vacuum tube, which is about the size of a human thumb, worked by using large amounts of electricity to heat a filament inside the tube until it was cherry red. One result of heating this filament up was the release of electrons into the tube, which could be controlled by other elements within the tube. De Forest's original device was a triode, which could control the flow of electrons to a positively charged plate inside the tube. A zero could then be represented by the absence of an electron current to the plate; the presence of a small but detectable current to the plate represented a one.

Transistors

Vacuum tubes were highly inefficient, required a great deal of space, and needed to be replaced often. Computers of the 1940s and 50s had 18,000 tubes in them and housing all these tubes and cooling the rooms from the heat produced by 18,000 tubes was not cheap. The transistor promised to solve all of these problems and it did so. Transistors, however, had their problems too. The main problem was that transistors, like other electronic components, needed to be soldered together. As a result, the more complex the circuits became, the more complicated and numerous the connections between the individual transistors and the likelihood of faulty wiring increased. In 1958, this problem too was solved by Jack St. Clair Kilby of Texas Instruments. He manufactured the first integrated circuit or chip. A chip is really a collection of tiny transistors which are connected together when the transistor is manufactured. Thus, the need for soldering together large numbers of transistors was practically nullified; now only connections were needed to other electronic components. In addition to saving space, the speed of the machine was now increased since there was a diminished distance that the electrons had to follow.

Circuit Board	Silicon Chip

Mainframes to PCs

The 1960s saw large mainframe computers become much more common in large industries and with the US military and space program. IBM became the unquestioned market leader in selling these large, expensive, error-prone, and very hard to use machines. A veritable explosion of personal computers occurred in the early 1970s, starting with Steve Jobs and Steve Wozniak exhibiting the first Apple II at the First West Coast Computer Faire in San Francisco. The Apple II boasted built-in BASIC programming language, color graphics, and a 4100 character memory for only $1298. Programs and data could be stored on an everyday audio-cassette recorder. Before the end of the fair, Wozniak and Jobs had secured 300 orders for the Apple II and from there Apple just took off.
Also introduced in 1977 was the TRS-80. This was a home computer manufactured by Tandy Radio Shack. In its second incarnation, the TRS-80 Model II, came complete with a 64,000 character memory and a disk drive to store programs and data on. At this time, only Apple and TRS had machines with disk drives. With the introduction of the disk drive, personal computer applications took off as a floppy disk was a most convenient publishing medium for distribution of software.
IBM, which up to this time had been producing mainframes and minicomputers for medium to large-sized businesses, decided that it had to get into the act and started working on the Acorn, which would later be called the IBM PC. The PC was the first computer designed for the home market which would feature modular design so that pieces could easily be added to the architecture. Most of the components, surprisingly, came from outside of IBM, since building it with IBM parts would have cost too much for the home computer market. When it was introduced, the PC came with a 16,000 character memory, keyboard from an IBM electric typewriter, and a connection for tape cassette player for $1265.
By 1984, Apple and IBM had come out with new models. Apple released the first generation Macintosh, which was the first computer to come with a graphical user interface(GUI) and a mouse. The GUI made the machine much more attractive to home computer users because it was easy to use. Sales of the Macintosh soared like nothing ever seen before. IBM was hot on Apple's tail and released the 286-AT, which with applications like Lotus 1-2-3, a spreadsheet, and Microsoft Word, quickly became the favourite of business concerns.
That brings us up to about ten years ago. Now people have their own personal graphics workstations and powerful home computers. The average computer a person might have in their home is more powerful by several orders of magnitude than a machine like ENIAC. The computer revolution has been the fastest growing technology in man's history.

Timeline

If you would like more detail, visit this annotated timeline with pictures and paragraphs on the important advances in computers since the 1940s.

Elizabeth I (r.1558-1603)

Elizabeth I (r.1558-1603)

Elizabeth I - the last Tudor monarch - was born at Greenwich on 7 September 1533, the daughter of Henry VIII and his second wife, Anne Boleyn.

Her early life was full of uncertainties, and her chances of succeeding to the throne seemed very slight once her half-brother Edward was born in 1537. She was then third in line behind her Roman Catholic half-sister, Princess Mary. Roman Catholics, indeed, always considered her illegitimate and she only narrowly escaped execution in the wake of a failed rebellion against Queen Mary in 1554.

Elizabeth succeeded to the throne on her half-sister's death in November 1558. She was very well-educated (fluent in six languages), and had inherited intelligence, determination and shrewdness from both parents.

Her 45-year reign is generally considered one of the most glorious in English history. During it a secure Church of England was established. Its doctrines were laid down in the 39 Articles of 1563, a compromise between Roman Catholicism and Protestantism.

Elizabeth herself refused to 'make windows into men's souls ... there is only one Jesus Christ and all the rest is a dispute over trifles'; she asked for outward uniformity.

Most of her subjects accepted the compromise as the basis of their faith, and her church settlement probably saved England from religious wars like those which France suffered in the second half of the 16th century.

Although autocratic and capricious, Elizabeth had astute political judgement and chose her ministers well; these included Burghley (Secretary of State), Hatton (Lord Chancellor) and Walsingham (in charge of intelligence and also a Secretary of State).

Overall, Elizabeth's administration consisted of some 600 officials administering the great offices of state, and a similar number dealing with the Crown lands (which funded the administrative costs). Social and economic regulation and law and order remained in the hands of the sheriffs at local level, supported by unpaid justices of the peace.

Elizabeth's reign also saw many brave voyages of discovery, including those of Francis Drake, Walter Raleigh and Humphrey Gilbert, particularly to the Americas. These expeditions prepared England for an age of colonisation and trade expansion, which Elizabeth herself recognised by establishing the East India Company in 1600.

The arts flourished during Elizabeth's reign. Country houses such as Longleat and Hardwick Hall were built, miniature painting reached its high point, theatres thrived - the Queen attended the first performance of Shakespeare's 'A Midsummer Night's Dream'. Composers such as William Byrd and Thomas Tallis worked in Elizabeth's court and at the Chapel Royal, St. James's Palace.

The image of Elizabeth's reign is one of triumph and success. The Queen herself was often called 'Gloriana', 'Good Queen Bess' and 'The Virgin Queen'.

Investing in expensive clothes and jewellery (to look the part, like all contemporary sovereigns), she cultivated this image by touring the country in regional visits known as 'progresses', often riding on horseback rather than by carriage. Elizabeth made at least 25 progresses during her reign.

However, Elizabeth's reign was one of considerable danger and difficulty for many, with threats of invasion from Spain through Ireland, and from France through Scotland. Much of northern England was in rebellion in 1569-70. A papal bull of 1570 specifically released Elizabeth's subjects from their allegiance, and she passed harsh laws against Roman Catholics after plots against her life were discovered.

One such plot involved Mary, Queen of Scots, who had fled to England in 1568 after her second husband's murder and her subsequent marriage to a man believed to have been involved in his murder.

As a likely successor to Elizabeth, Mary spent 19 years as Elizabeth's prisoner because Mary was the focus for rebellion and possible assassination plots, such as the Babington Plot of 1586.

Mary was also a temptation for potential invaders such as Philip II. In a letter of 1586 to Mary, Elizabeth wrote, 'You have planned ... to take my life and ruin my kingdom ... I never proceeded so harshly against you.' Despite Elizabeth's reluctance to take drastic action, on the insistence of Parliament and her advisers, Mary was tried, found guilty and executed in 1587.

In 1588, aided by bad weather, the English navy scored a great victory over the Spanish invasion fleet of around 130 ships - the 'Armada'. The Armada was intended to overthrow the Queen and re-establish Roman Catholicism by conquest, as Philip II believed he had a claim to the English throne through his marriage to Mary.

During Elizabeth's long reign, the nation also suffered from high prices and severe economic depression, especially in the countryside, during the 1590s. The war against Spain was not very successful after the Armada had been beaten and, together with other campaigns, it was very costly.

Though she kept a tight rein on government expenditure, Elizabeth left large debts to her successor. Wars during Elizabeth's reign are estimated to have cost over £5 million (at the prices of the time) which Crown revenues could not match - in 1588, for example, Elizabeth's total annual revenue amounted to some £392,000.

Despite the combination of financial strains and prolonged war after 1588, Parliament was not summoned more often. There were only 16 sittings of the Commons during Elizabeth's reign, five of which were in the period 1588-1601. Although Elizabeth freely used her power to veto legislation, she avoided confrontation and did not attempt to define Parliament's constitutional position and rights.

Elizabeth chose never to marry. If she had chosen a foreign prince, he would have drawn England into foreign policies for his own advantages (as in her sister Mary's marriage to Philip of Spain); marrying a fellow countryman could have drawn the Queen into factional infighting. Elizabeth used her marriage prospects as a political tool in foreign and domestic policies.

However, the 'Virgin Queen' was presented as a selfless woman who sacrificed personal happiness for the good of the nation, to which she was, in essence, 'married'.
Late in her reign, she addressed Parliament in the so-called 'Golden Speech' of 1601 when she told MPs: 'There is no jewel, be it of never so high a price, which I set before this jewel; I mean your love.' She seems to have been very popular with the vast majority of her subjects.

Overall, Elizabeth's always shrewd and, when necessary, decisive leadership brought successes during a period of great danger both at home and abroad. She died at Richmond Palace on 24 March 1603, having become a legend in her lifetime. The date of her accession was a national holiday for two hundred years.

World War II

World War II, also called Second World War,  conflict that involved virtually every part of the world during the years 1939–45. The principal belligerents were the Axis powers—Germany, Italy, and Japan—and the Allies—France, Great Britain, the United States, the Soviet Union, and, to a lesser extent, China. The war was in many respects a continuation, after an uneasy 20-year hiatus, of the disputes left unsettled by World War I. The 40,000,000–50,000,000 deaths incurred in World War II make it the bloodiest conflict, as well as the largest war, in history.

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Along with World War I, World War II was one of the great watersheds of 20th-century geopolitical history. It resulted in the extension of the Soviet Union’s power to nations of eastern Europe, enabled a communist movement to eventually achieve power in China, and marked the decisive shift of power in the world away from the states of western Europe and toward the United States and the Soviet Union.

Axis initiative and Allied reaction

The outbreak of war

By the early part of 1939 the German dictator Adolf Hitler had become determined to invade and occupy Poland. Poland, for its part, had guarantees of French and British military support should it be attacked by Germany. Hitler intended to invade Poland anyway, but first he had to neutralize the possibility that the Soviet Union would resist the invasion of its western neighbour. Secret negotiations led on August 23–24 to the signing of the German-Soviet Nonaggression Pact in Moscow. In a secret protocol of this pact, the Germans and the Soviets agreed that Poland should be divided between them, with the western third of the country going to Germany and the eastern two-thirds being taken over by the U.S.S.R.

Having achieved this cynical agreement, the other provisions of which stupefied Europe even without divulgence of the secret protocol, Hitler thought that Germany could attack Poland with no danger of Soviet or British intervention and gave orders for the invasion to start on August 26. News of the signing, on August 25, of a formal treaty of mutual assistance between Great Britain and Poland (to supersede a previous though temporary agreement) caused him to postpone the start of hostilities for a few days. He was still determined, however, to ignore the diplomatic efforts of the western powers to restrain him. Finally, at 12:40 pm on August 31, 1939, Hitler ordered hostilities against Poland to start at 4:45 the next morning. The invasion began as ordered. In response, Great Britain and France declared war on Germany on September 3, at 11:00 am and at 5:00 pm, respectively. World War II had begun.