Describe the early computing machines and their inventors in the dark age.

DEVICES USED IN DARK AGE 

1. Abacus 

About 5,000 years ago 'abacus' was invented in China. It is considered as the first computer. It is a rectangular frame with vertical wires containing a number of beads for representing units, tens, hundreds, thousands and so on. Calculations were done by moving the beads along with the wires. The structure of abacus is divided into two parts, the upper part is called the 'HEAVEN' and lower part the 'EARTH'. 

2. Napier's Rods 

In 1612, John Napier made the first printed use of the decimal point and invented logarithms and he designed a device called Napier's rods or bones. This device consisted of a set of eleven rods or bones with number marked on them. By placing these rods side by side products and quotients of large numbers could be obtained very easily. 

3. Oughtred's Slide rule 

In 1622, Oughtred developed a slide rule based on Napier's logarithms that was uses! by engineers as primary calculator. It was consisted of two movable rulers placed side by side. Each ruler is marked in such a way that the actual distances from the beginning of the ruler are proportional to the logarithm of the numbers printed on the ruler. By sliding the rulers multiplication and division could be done quickly. 

4. Pascaline (Pascal's Calculator) 

In 1640a French mathematician, Blaise Pascal started developing a device to add sums of money. In 1642 he invented the first operating model a numerical wheel calculator. This brass rectangular box,also called a Pascaline, used 8 movable dials to add numbers upto eight figures long. Pascal's device used a base of ten to accomplish this. It could perform addition and subtraction only, while multiplication and divisions were implemented by performing a series of addition and subtractions. In fact this device could really only add, because subtractions were performed using complement techniques. Modern computers use similar complement techniques for subtraction. 

5. G.W. Leibniz's 

Calculator Leibniz improved on Pascal's calculator in 1694 by creating a machine, that could also multiply. Leibniz's mechanical multiplier worked by a system of gears and dials. 

6. Jacquard's Loom 

In ( 820 French Weaver Joseph Marie Jacquard invented the first punch card to control the patterns to be woven. Jacquard's Loom is considered the first significant use of binary automation. 

7. Arithometer 

Charles Xavier Thomas de Colmar, a Frenchman invented a machine in 1820 that could perform the four basic arithmetic operations. Colmar's mechanical calculator, the Arithometer, presented a more practical approach to computing 

HISTORY AND DEVELOPMENT OF COMPUTER

Into how many ages is the computer era divided 

AGES OF THE COMPUTER ERA 

The computer era is divided into three ages: 
1. The Dark Age (5000 B.C. to 1890 A.D.) 
2. The Middle Age ( 1890 A.D. to 1944 A.D.) 

What are the limitations of the computers

LIMITATIONS OF THE COMPUTERS 

1. No ability to generate Information 

A computer cannot generate information on its own. 

2. No ability to correct 

A computer cannot correct wrong instructions. 

3. No decision at its own 

A computer cannot come up with an original decision. 

What are the Capabilities of computer

CAPABILITIES OF COMPUTER 

1. Speed 

A Computer can process data faster than any other machine designed to perform a similar task. 

2. Repetitions 

A computer can tirelessly perform the same operations millions of times in exactly the same way without getting bored and tired as a human clerk would. 

3. Accuracy 

A computer's high-speed processing is accompanied by high-accuracy results. No other system can have as much accuracy as a computer system. 

4. Logical operations

The computer can make decision based on some conditions and take alternative course of action accordingly. 

5. Store and recall information 

The computer is like human brain as it can store facts, instructions and information and recall them when needed. 

6. Self-checking 

The computer verifies the accuracy of its own work by means of a parity check. 

7. Self-operating 

Once the data and program are fed into the computer memory, the computer is capable of executing the instructions on its own, without human intervention. 

Describe some of the characteristics of computers.

CHARACTERISTICS OF COMPUTER 

1. Machine:

It is a machine. It is an inanimate object. It needs outside intervention for it to run. It can only do things for which it is designed. 

2. Electronic:

It is Electronic because it is made up of electronic circuits. It runs on electrical energy. 

3. Automatic:

It is automatic. Once started it continues to run without outside intervention. 

4. Data Manipulator:

It can manipulate data, following specific rules. It can perform arithmetic functions such as addition, subtraction, multiplication, and division. It can compare data.

 5. Memory: 

It has memory. It has the capacity to remember what it has done. It can store instructions in its memory and follow these through unaided. 

Write a note on Software.

SOFTWARE DEFINITION

Software refers to the programs that instruct the computer what to do. Software makes the computer useful. Software is the set of all the programs (instructions) and data necessary to make the computer usable.

Examples Windows

Visual Basic, Norton antivirus, Microsoft Word, Microsoft Excel etc.

TYPES OF SOFTWARE

Software are of two types. 
• System Software 
• Application Software 

Write a note on Hardware.

HARDWARE DEFINITION

The physical or tangible components forming a computer are called Hardware. When people talk about a computer, they usually mean the hardware.

Or 

The physical components of computer and other attached input ad output devices are called hardware. 

COMPONENTS OF HARDWARE 

Hardware is a collective term. All hardware components may be connected mechanically electrically or electronically with each other. It includes the cables, connecters, power supply units and peripheral devices such as.

• Keyboard 
• Mouse 
• Audio speakers 
• Printers 

Define Computer

DEFINITIONS OF COMPUTER

Computer is an electronic device that accepts data and instructions (in form of programs) as input, processes that data according to the given instructions and produces information as output.

OR

Computer is a machine that can accept input data, processes it and gives output.

OR

A computer is an electronic device that can interpret and execute programmed commands for input, output, computation and logic operations.

OR

A computer is an automatic electronic calculating device which can process given data and gives results.

OR

A computer is a device capable of accepting data and gives desired result by processing.

OR

A computer is a device which processes the given data with the help of a stored program at high speed.