Data processing

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DataData is a collection of facts & figures, such as values or

measurements.

It can be

a) numbers, b) words, c) measurements, d) observations or even just descriptions of things.

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InformationA collection of data which conveys some meaningful idea is

called information.

or

When data is collated or organized into meaningful form, it gains significance. This meaningful data is called information.

e.g. Aslam is a student of Phram-D class.

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DataThe word data is derived from Latin language. Data is any collection of raw facts & figures. The data is the raw material to be processed by a computer. or anything that is input to the computer is called data.

ExampleNAMES of students, Marks obtained in the examination, Designation of employees, addresses, Quantity, rate, sales figures Pictures, photographs, drawings, charts and maps can be treated as data.

Computer processes the data and produces the output.

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Types of DataHave two types:

- Numeric Data, - Character Data

1. Numeric Data: The data which is represented in the form of numbers is known as Numeric Data. Includes 0-9 digits, a decimal point (.), +, /, – sign and the letters

2. Character Data: Character data falls into two groups.

i. String Data, ii. Graphical Data

String Data: String data consists of the sequence of characters.

• Characters may be alphabets, numbers or space. • The space, which separates two words, is also a

character.• The string data is further divided into two types.

a. Alphabetic Data: a to zb. Alphanumeric Data: a to z & decimal numbers

Graphical Data: It is possible that pictures, charts and maps can be treated as data. The scanner is normally used to enter this type of data.

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Data Processing

Data processing:

Any operation or set of operations performed upon data,

Such as • collection, • recording, • organization,

• Storage or alteration to convert it into useful information.

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Data Processing Cycle

Once data is collected, it is processed to convert it into useful information. The data is processed again and again until the accurate result is achieved. This is called data processing cycle.

The data processing is very important activity and involves very careful planning. Usually, data processing activity involves three basic activities.

1. Input 2. Processing 3. Output

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Data Processing Cycle…Step-1

1. Input: It is the process through which collected data is transformed into a form that computer can understand. It is very important step because correct output result totally depends on the input data. In input step, following activities can be performed.

i) CodingThe verified data is coded or converted into machine readable form so that it can be processed through computer.

ii) VerificationThe collected data is verified to determine whether it is correct as required.

e.g. The collected data of all B.Sc. students that appeared in final examination of the university is verified. If errors occur in collected data, data is corrected or it is collected again.

iii) StoringThe data is stored on the secondary storage into a file. The stored data on the storage media will be given to the program as input for processing.

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Data Processing Cycle…

Step-2 Processing

The term processing denotes the actual data manipulation techniques

such as

•classifying, •sorting, •calculating, •summarizing, •comparing, etc.

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Data Processing Cycle

Step-3 Output

•After completing the processing step, output is generated.

•The main purpose of data processing is to get the required result.

•The output is stored on the storage media for later use.

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Computer Processing Operations

A process is an instance of a computer programThat is being executed. It contains the program code and its current activity. A computer can perform four operations whichenable computers to carry out the various dataprocessing activities.

• Input / Output operations • Calculation/ text manipulation Operations• Logic / Comparison Operations • Storage and Retrieval Operations

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(A) Input/Output operations

A computer can accept data (input) from and processed data.

Input devices like keyboards, display screens,Printers is just like output device.

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(B) Calculation and Text manipulation Operations

ALU( arithmetic and logical unit) performs calculation.

They are also capable of manipulating numeric and other symbols used in text.

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(C) Logic/Comparison Operations

A computer also possesses the ability to perform logical operations.

For example, Compare two items represented by the symbols A and B, there are only three possible outcomes e.g. grad etc.

A is less than B (A<B)A is equal to B (A=B)A is greater than B (A>B)

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(D) Storage and Retrieval Operations

Both data and program instructions are stored internally in a computer.

Once they are stored in the internal memory, they can be called up quicklyor retrieved for further use.

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Types of Data Processing

1. Manual Data Processing

2. EDP

3. Real time processing

4. Batch processing

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1- Manual Data Processing:Definition: Manual data processing it's done with pen & paper

With traditional data processing method's.

or

The manual process of data entry implies many opportunities

for errors, such as

Delays in data capture, A high amount of operator misprints, High labor costs from the amount of manual

labor required etc.

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EDP: (electronic data processing),

Definition: Use of computers for recording, manipulating, and summarizing data.

EDP can refer to the use of automated process commercial data. Thisuses relatively simple, repetitive activities to process large volumes ofsimilar information.

e.g. Stock updates applied to an inventory, Banking transactions applied to account and customer master files, Booking and ticketing transactions to an airline's reservation system, Billing for utility services.

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3.Real time processing

Real time processing, there is a continual input, process and output of data. Data has to be processed in a small time period (real time).

e.g. A bank customer withdraws a sum of money from his or her account it is vital that the transaction be processed and the account balance updated as soon as possible, allowing both the bank and customer to keep track of funds.

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4.Batch processingDefinition: In Batch processing group of transactions collected over a period of time is collected, entered, processed and thenthe batch results are produced. orBatch processing requires separate programs for input, process and output. It is an efficient way ofprocessing high volume of data.

For example:

Payroll system, Examination system. Etc.

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