MODULE 1
Basic Computing Concepts
A computer can be described as an electronic device that accepts data as input, processes the
data based on a set of predefined instructions called program to produce the result of these
operations as output called information. From this description, a computer can be referred to as
an Input-Process-Output (IPO) system, pictorially represented in the Figure 1:
INPUT PROCESS OUTPUT
Figure 1.1: IPO Representation of a computer System
Data are raw facts, such as a score in examination or the name of a student, for example 55 or
Malik respectively. There are three types of data – Numeric, alphabetic, and alphanumeric.
Numeric data consists of digits 0 – 9 (such as 31), while alphabetic data consist of any of the
English language alphabets in upper and lower cases (e. g. Toyin). An alphanumeric data can
consist of a number, an alphabet or a special character, such as a vehicle plate number (e. g. AE
731 LRN).
Information: data as described above contain no meaning, however, when it is transformed into
a more meaningful and useful form, it is called information. The transformation process
involves a series of operations to be performed by the computer on the raw data that are fed into
the system. The operation can be arithmetic (such as addition, subtraction, multiplication, and
division), logical comparison or character manipulation (as in text processing).
Logical comparison means testing whether one data item is greater than, equal to, or less than
another item, and based on the outcome of the comparison, a specified action can be taken. The
output of the processing can be in form of reports which can be displayed or printed.
The History of Computer
In the early days of man, fingers and toes were used for counting. Later on, sticks and pebbles
were used. Permanent records of the result of counting were kept by putting marks on the
ground, wall and so on using charcoal, chalk, and plant juice.
The historical development of computing focuses on the digital computer from the Abacus to the
modern electronic computer. Some of these people whose contributions have been widely
acknowledged to the development of Computer will be discussed:
Abacus
The abacus was invented to replace the old methods of counting. It is an instrument known to
have been used for counting as far back as 500 B.C. in Europe, China, Japan and India and it is
still being used in some parts of China today.
The abacus qualifies as a digital instrument because it uses beads as counter to calculate in
discrete form. It is made of a board that consists of beads that slide on wires. The abacus is
divided by a wooden bar or rod into two zones. Perpendiculars to this rod are wires arranged in
parallel, each one representing a positional value. Each zone is divided into two levels - upper
, and lower. Two beads are arranged on each wire in the upper zone, while five beads are
arranged on each wire in the lower zone.
The abacus can be used to perform arithmetic operations such as addition and subtraction
efficiently.
Figure 1.2: Modern abacus.
Note that the abacus is really just a representation of the human fingers: the 5 lower rings
on each rod represent the 5 fingers and the 2 upper rings represent the 2 hands.
Blaise Pascal
Pascal was born at Clermont, France in 1623 and died in Paris in 1662. Pascal was a Scientist as
well as a Philosopher. He started to build his mechanical machine in 1640 to aid his father in
calculating taxes. He completed the first model of his machine in 1642 and it was presented to
the public in 1645.
The machine, called Pascal machine or Pascaline, was a small box with eight dials that
resembled the analog telephone dials. Each dial is linked to rotating wheel that displayed the
digits in a register window. Pascal’s main innovative idea was the linkage provided for the
wheels such that an arrangement was made for a carry from one wheel to its left neigbour when
the wheel passed from a display of 9 to 0. The machine could add and subtract directly.
Figure 1.3: Pascal's Pascaline [photo © 2002 IEEE]
A Pascaline opened up so you can observe the gears and cylinders which rotated to display
the numerical result
Joseph Marie Jacquard
In 1801 the Frenchman Joseph Marie Jacquard invented a power loom that could base its weave
(and hence the design on the fabric) upon a pattern automatically read from punched wooden
Basic Computing Concepts
A computer can be described as an electronic device that accepts data as input, processes the
data based on a set of predefined instructions called program to produce the result of these
operations as output called information. From this description, a computer can be referred to as
an Input-Process-Output (IPO) system, pictorially represented in the Figure 1:
INPUT PROCESS OUTPUT
Figure 1.1: IPO Representation of a computer System
Data are raw facts, such as a score in examination or the name of a student, for example 55 or
Malik respectively. There are three types of data – Numeric, alphabetic, and alphanumeric.
Numeric data consists of digits 0 – 9 (such as 31), while alphabetic data consist of any of the
English language alphabets in upper and lower cases (e. g. Toyin). An alphanumeric data can
consist of a number, an alphabet or a special character, such as a vehicle plate number (e. g. AE
731 LRN).
Information: data as described above contain no meaning, however, when it is transformed into
a more meaningful and useful form, it is called information. The transformation process
involves a series of operations to be performed by the computer on the raw data that are fed into
the system. The operation can be arithmetic (such as addition, subtraction, multiplication, and
division), logical comparison or character manipulation (as in text processing).
Logical comparison means testing whether one data item is greater than, equal to, or less than
another item, and based on the outcome of the comparison, a specified action can be taken. The
output of the processing can be in form of reports which can be displayed or printed.
The History of Computer
In the early days of man, fingers and toes were used for counting. Later on, sticks and pebbles
were used. Permanent records of the result of counting were kept by putting marks on the
ground, wall and so on using charcoal, chalk, and plant juice.
The historical development of computing focuses on the digital computer from the Abacus to the
modern electronic computer. Some of these people whose contributions have been widely
acknowledged to the development of Computer will be discussed:
Abacus
The abacus was invented to replace the old methods of counting. It is an instrument known to
have been used for counting as far back as 500 B.C. in Europe, China, Japan and India and it is
still being used in some parts of China today.
The abacus qualifies as a digital instrument because it uses beads as counter to calculate in
discrete form. It is made of a board that consists of beads that slide on wires. The abacus is
divided by a wooden bar or rod into two zones. Perpendiculars to this rod are wires arranged in
parallel, each one representing a positional value. Each zone is divided into two levels - upper
, and lower. Two beads are arranged on each wire in the upper zone, while five beads are
arranged on each wire in the lower zone.
The abacus can be used to perform arithmetic operations such as addition and subtraction
efficiently.
Figure 1.2: Modern abacus.
Note that the abacus is really just a representation of the human fingers: the 5 lower rings
on each rod represent the 5 fingers and the 2 upper rings represent the 2 hands.
Blaise Pascal
Pascal was born at Clermont, France in 1623 and died in Paris in 1662. Pascal was a Scientist as
well as a Philosopher. He started to build his mechanical machine in 1640 to aid his father in
calculating taxes. He completed the first model of his machine in 1642 and it was presented to
the public in 1645.
The machine, called Pascal machine or Pascaline, was a small box with eight dials that
resembled the analog telephone dials. Each dial is linked to rotating wheel that displayed the
digits in a register window. Pascal’s main innovative idea was the linkage provided for the
wheels such that an arrangement was made for a carry from one wheel to its left neigbour when
the wheel passed from a display of 9 to 0. The machine could add and subtract directly.
Figure 1.3: Pascal's Pascaline [photo © 2002 IEEE]
A Pascaline opened up so you can observe the gears and cylinders which rotated to display
the numerical result
Joseph Marie Jacquard
In 1801 the Frenchman Joseph Marie Jacquard invented a power loom that could base its weave
(and hence the design on the fabric) upon a pattern automatically read from punched wooden
