Information Technology Centre

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When handling data remember the acronym GIGO which stands for Garbage In Garbage Out. Failure to enter accurate data always result in faulty output.

What is data?

DATA is raw facts and figures and by itself DATA is meaningless. The word 'data' is a plural noun. A single item of data is called ' datum'.

When we collect data we are collecting :

  1. Facts
  2. Figures
  3. Symbols

Data is raw facts, symbols and figures we collect about any person, place, animal or thing. After we collect and verify that the data we collect is accurate then and only then should we process or organize the data so that it becomes meaningful and appropriate for decision making. Some companies gather that data and sell it to others for profit. We should be careful to keep our personal data private and not give it away freely for others to profit from it.

Collecting data for input is called data capture and it is the first stage in the data-processing cycle.

Information is obtained from data after the data is verified and processed or organized. The information we obtain after processing data is then used for decision making. Information can be bought or sold so information is a commodity. It is important to note here that information IS NOT data.

Types of data

There are two different types of data

There are TWO types of DATA:

  1. Quantitative data
  2. Qualitative data

The stage in the data processing cycle which follow data capture is called DATA PREPARATION. It is at this stage data is verified and validated.

Quantitative data

Quantitative data is numeric data. Data that is in the form of numbers.

Examples of DISCRETE NUMERIC data values

  1. The number of days in a week
  2. The number of children on a bus
  3. The number of cars in a parking lot

Examples of CONTINUOUS NUMERIC data values

  1. The weight of a person
  2. The height of the tallest boy in a class

Qualitative or categorical data

Qualitative data has no order and are more of a descriptive nature.

Examples QUALITATIVE data values

  1. blue shirt
  2. small house
  3. fast car
  4. dangerous drive
  5. noisy child

How Is Data Represented in a Computer?

Data is represented in a computer by means of millions of simple on/off electronic switches. When a switch is in the ON state we use 1 to represent that state. When a switch is in the OFF state the digit 0 is used. This is the binary number system. Binary is the simplest language known to man. The smallest amount of data a computer can manipulate is a BIT or binary digit (0 or 1).

Data vs Information

Data and Information ARE NOT the same things. After data is collected, it is processed to convert it into useful information.

Here is a simple example of DATA that is not organized in any meaningful way : RTUMPOCE. These letters do not convey any meaning but when we rearrange the letters we will get a meaningful word. Re-arrange the letters and you will have produced information.

Data integrity

Every effort must be made to ensure that data is accurate and complete when it enters a computer system. Once entered, the data must be protected to ensure it is not altered, corrupted or deleted by unautorised persons. When data is complete and accurate we say it has data integrity.

Data security

Data security is about protecting data from unauthorised access. To accomplish this data must be protected using both physical and software safequards. Physical data security involves alarms, locks and security guards. Software protection includes the use of strong passwords, audit trails or access logs and data encryption.

Test Yourself

Choose the correct answer
Questions Options Verify
 1)  Data should be protected by physical as well as software measures True
False
 2)  Computers correct the errors users input True
False
 3)  The number 5,000 represents qualitative data True
False
 4)  The color BLUE represents qualitative data True
False
 5)  The number 6 for the days of creation is quantitative data True
False
 6)  The smallest amount of data a computer can processs is a bit True
False

Assignment 1.2

1. All the physical components of a computer :

a) mouse       b) motherboard      c) hardware       b) cpu


2. All computer programs :

a) microsoft word       b) excel      c) joystick       d) software


3. Converting data into information is called ...

a) input       b) processing      c) storage       d) output


4. Which device is the most important?

a) cpu       b) keyboard      c) monitor       d) printer


5. A group of two or more computers sharing data

a) network       b) wifi      c) internet       d) modem


6. Which of the following is NOT an example of a peripheral device?

a) mouse       b) RAM      c) speaker       d) keyboard


7. The ALU processes data and stores it in ...

a) main memory (RAM)       b) ROM      c) hard disk       d) flash drive


8. Collecting data for input is called ...

a) data processing       b) hacking      c) networking       d) data capture


9. Carefully checking what has been typed against the original document is called.

a) data security       b) data checking      c) proofreading       d) validation


10. Checking a field on a form to ensure data is entered and it is not left blank

a) presence check       b) length check      c) range check       d) format check


GROUP 1

Unscramble this list of 10 data items to convert from raw data into meaningful IT words (information) :

  1. I K D S
  2. E S U M O
  3. E I D E V C
  4. P O T A L P
  5. G E A O T S R
  6. T O R N M O I
  7. R T I R P N E
  8. T T U U O P
  9. E A P S E K R
  10. R N C S A N E