Computer Fundamentals
Chapter 1
I. Introduction
Computer – a general purpose device which can be programmed to carry out a finite set of
arithmetic or logical operations.
- It is an electronic device that receives instructions for processing from the user to
produce the required outcome.
- A machine for manipulating data according to sequence of instructions.
- Comes from the root word “compute” meaning to calculate.
- It all started from the abacus and up to the 1900s computing devices can perform
the four basic operations of adding, subtracting, multiplying and dividing numbers.
During the late 20th century showed an expansion of the computers function but not
departing from its original purpose.
II. Functions of Computers
1. Perform Calculations. Calculations are not limited to performing calculator functions (ex.
Four basic operation and scientific functions) but can perform more complex statistical
computations and linear programming computations to name a few. Various computer
software, are available for more complex computations.
2. Word Processing. Computers have replaced the typewriter and for word processing
become the primary purpose for using computers.
3. Storing Information. Another purpose of the computer is it helps in the reduction of files
(papers) in offices. In place of papers files are stored in the hard disk drives of the
computer and/or optical disk also known as compact disk.
4. Communications. This makes the world look smaller. Through the web people can
communicate with each other real time or send e-mail (electronic mail).
Communications through the use of a computer make letter sending obsolete.
5. Entertainment. Computers are capable of playing audio CDs, MP3s, and movies in VCD
or DVD format. Popular forms of entertainment in computers are games. Games are
played individually or with a small group and even a large group for web-based games.
6. Simulation. Simulation represents real life situations. Some companies run simulations
as a more cost effective measure before producing the actual product or in making a
decision. Airplane pilots train using flight simulation programs. Automobile
manufacturers conduct testing of their vehicles through simulation before producing the
unit.
7. Computer Programming. Computers are used to develop programs for all types of
industries.
8. Production process. In a manufacturing company computers are used to make sure
quality is consistent throughout production. Computers are also used to operate the
machines therefore, reducing the need for manpower.
9. Processing of Transaction. In non-manufacturing companies, computers are used to
process transaction. An example is the banking system, where the computers located in
the different branches are connected to a large network together with the Automated
Teller Machines (ATMs) and other head office units to process transactions.
10. Special Project. Being multi-purpose device, users can create home movies from
photographs that they have taken, create greeting cards, voice recordings, edit pictures,
etc.
11. Robotics. Computers have been used to program robots to function according to the
purpose in which they were built. Various companies have started developing robots and
continuous research is being made regarding this field.
12. Artificial Intelligence. Making computers perform like humans. For example, robots have
been programmed to walk, communicate, etc.
III. History of computers
The earliest recorded computer is the abacus. The abacus consists of a frame with rods and
beads, which are moved along the rods. There is no account as to who invented the abacus but it
was used by different countries but is still being used by Chinese.
John Napier (1550-1617)- invented the abacus-like computing device called the Napier’s Bones.
The calculator can perform multiplication and division calculations. The Napier’s Bones is based
on Arab mathematics and lattice multiplication.
Wilhelm Schickard (1592-1635)- invented the first known mechanical calculator that can
perform addition, subtraction, multiplication and division, but remained unknown for 300 years.
Only two (2) models were built by Schickard one was lost in a fire and the other after his death.
Some call his invention the “speeding clock” or “calculating clock”
Blaise Pascal (1623-1661) made his version of the mechanical calculator in 1642. It was designed
to help his father in his work as a tax collector. The gear driven calculator can only perform
addition and subtraction. Only fifty (50) of these expensive machines were built and were
purchased mostly by the rich.
Gottfried Wilhelm Leibniz (1646-1716) created in the 1671s a mechanical calculator called the
“stepped reckoner” that can perform addition, subtraction, multiplication and division. It is
made of brass and steel enclosed in an oak case. It has an eight (8) digit input portion in front
accumulator at the back of the machine that displays the result up to sixteen (16) decimal digits.
Parts lack precise construction, which sometimes resulted in inaccurate calculations. This was
due to the stringent design of the calculating machine that no one at that time could construct.
Charles Babbage (1791-1871) developed the first programmable machine called the “analytical
engine”. The design uses punched cards to store programs and run the machine. It was intended
to reduce if not eliminate errors in computing. The machine was never completed. Limited
technology in producing the parts for the machine became an obstacle for Babbage as well as
the machine being large in size. The bulk of the machine would have been around 30 meters in
length and 10 meters in width.
Herman Hollerith (1860-1929) developed a mechanical tabulator in 1890 for the United States
Census Bureau in 1890. The mechanical tabulator was based on punched cards to tabulate large
volume of statistical data. The machine used electricity to power the machine. The machine has
cards passing through needles that read the holes in the cards. This triggers a counter to record
and compute the data.
In 1880 it took 8 years to compute the data for Census Bureau. Using the mechanical tabulator in
1890 took only one year to compute all the data and without it will take ten years to complete
the computations.
Hollerith founder of Tabulating Machine Company and merged with two other companies in
1911 to form Computing Tabulating Recording Corporation (CTR) and in 1924 changed the name
to International Business Machines (IBM).
In the 1936, Alan Turing created a theoretical computing machine known as the “Turing
Machine”. The machine consists of a Tape that contains cells, a Head to read and write symbol
on the tape, a Table is the sequence of instructions that the machine follows and the State
Register stores the position or status of the Turing Machine.
John William Mauchly and John Presper Eckert of the University of Pennsylvania developed the
first general purpose electronic digital computer called ENIAC (Electronic Numerical Integrator
and Computer) in 1946. ENIAC was designed and built for use by the military. The machine was
used to compute artillery firing tables for the U.S. Army. Computation was slow as it could only
perform hundreds of computations per minute.
The ENIAC is large in size containing 17, 468 vacuum tubes, 70, 000 resistors, 10, 000 capacitors,
1, 500 relays, 6, 000 manual switches and 5 million soldered joints. It covered 167 square meters
of floor space, weighed 30 tons and consumed 160 kilowatts of electrical power.
EDSAC (Electronic Delay Storage Automatic Calculator) a stored-program computer was built by
Sir Maurice Wilks and his team at the University of Cambridge Mathematical Laboratory in 1949.
Though, it was Jon von Neumann of the Institute for Advance Study who introduced the concept
of stored-program computers.
John William Mauchly and John Presper Eckert after creating the ENIAC left Moore School and
formed their own company Electronic Control Company. The company was renamed EckertMauchly Computer Corporation in 1946. They sold their company to Remington Rand in 1950.
Remington Rand merged with Sperry Corporation and became known as Sperry Rand. The
company was sold in the mid-1950s to International Business Machines (IBM).
Mauchly and Eckert created UNIVAC 1 (Universal Automatic Computer) under Remington Rand
in 1951. Moving away from the punched tape the UNIVAC uses magnetic tape instead, for
storing alphabetical and numerical data. UNIVAC was produced commercially and 48 machines
were sold.
Minicomputers emerged in the 1960s. This is a significant improvement from previous computer
designs by creating smaller, more powerful and cheaper machines. Although, one may not be
convinced that it deserves the “mini” connotation as it occupies a lot of space.
Integrated circuit (IC) is a small electronic circuit and was used in minicomputers during the
1960s. The reason for the large size of the ENIAC is that it uses of 17, 468 vacuum tubes and with
the vacuum tubes size makes it heavy and expensive to produce as well. The use of ICs in
computers significantly reduced the size of computers.
Very-Large-Scale Integration (VLSI) is the process placing thousands of electronic circuit
components into a chip. The microprocessor is an example of a VLSI device.
Steve Jobs and Steve Wozniak in 1976 produced by hand the Apple I computer. But it wasn’t
until 1977 when they produced the Apple II computer, which eventually became a benchmark
for Personal Computers (PC).
The Apple II is more technologically advanced than the Apple I thus making Apple II a
commercial success that other manufacturers began producing their own version of the PC.
More than five (5) million Apple II personal computers were produced up to the 1990s.
In August 1981, IBM launched their version of the PC and was to compete with Apple II. This will
eventually be copied or “cloned” by numerous manufacturers. IBM “compatible” computers will
eventually flood the market as branded computer parts become readily available and are easy to
assemble.
Steve Chen designed the supercomputer Cray X-MP under Cray Research, Inc. Produced in 1982
and became the world’s fastest computer from 1983-1985. The computer uses multiple
processors to speed up processing of data. In 2000, Tera Computer Company bought Cray
Research, Inc. and formed Cray, Inc. the movie The Last Starfighter used the super computer for
its graphical effects. The cost ranges from $7million to $17million during the time it was
introduced.
Historians considered the Gavilan SC of Manuel Fernandez founder of Gavilan Computer as the
Starting point of laptop computers. The computer was produced in 1983.
The Gavilan SC uses an Intel 8088 processor, has a floppy disk drive, LCD screen and used an MSDOS operating system.
In 1984, the first personal digital assistant (PDA) also known as pocket computer, handheld
computer, palm or palmtop computer was the Psion Organizer. The Psion Organizer uses a
keypad to enter text.
1993 saw the release of the Apple Computers’ PDA called Newton in the market. The Newton
became the first popular brand of PDA. The Newton uses a light pen to enter text but has its
shortcomings as it has problems recognizing poor handwriting.
IV. Generation of Computers
1. The First Generation (1951-1959). The first generation of computers started with the
UNIVAC I. Computers during this generation used vacuum tubes. First generation
computers were programmed using binary number system (0s and 1s). In 1952, Dr.
Grace Hopper from the University of Pennsylvania developed the first program
translators.
2. The Second Generation (1959-1965). The second generation saw the development of
high level programming languages such as FORTRAN (Formula Translator) in 1957 and
COBOL (Common Business Oriented Language) in 1961. Operating systems and
compilers were developed. Second Generation computers used transistors. Computers
during this generation started using magnetic tape and disk for data storage.
3. The Third Generation (1965-1970). This generation started with the introduction of the
IBM 360. This marked the start in the use of integrated circuits which reduced the size of
computers. Significant improvements in computer development marked this generation
in terms of processing speed, accuracy, integration of hardware and software processing
performance and data communications.
4. The Fourth Generation (1970-Present). The fourth generation started with the use of
large scale integration (LSI) and the development of microprocessors and
microcomputers. The cost or purchasing a computer unit dropped significantly. Software
development vastly improved as more-and-more high level languages were introduced.
Notable improvements in data communications, operating systems, compilers and utility
programs which expanded the use of computers.
V. Types of computers
1. Analog. Used for measuring electric current or voltage levels and hydraulic pressure for
example. They are fast but not accurate since variables are changing and they can only
give estimate of the result.
2. Digital. Perform calculations and provide an accurate result.
3. Hybrid. It is a mix of analog and digital computer.
4. Special Purpose. Designed to perform a specific job or function.
VI. Three parts of computer environment.
1. Hardware. This refers to the physical aspect of the computer. There are four categories
of computer hardware:
a. Input Device. This is what the user will use to instruct the computer of the activity
that it will perform.
Ex. Keyboard, Mouse, Light Pen, and Scanner
b. Processing Device. This is where instructions are processed.
Ex. System Unit
c. Output Device. This is where the result of processing of the instructions proceeds to.
Ex. Monitor, Printer, Projector, Speakers, Earphones, and Headset
d. Storage Units. It is where computer programs and files are stored.
Ex. Hard Disk Drive, Compact Disc and Digital Video Disc, Flash Memory, Random
Access Memory.
2. Software. These are the computer programs installed in the computer. The software
performs a variety of functions like file maintenance, word processing, entertainment,
etc.
3. Peopleware. They are the users of the computer.