What is data?
Data is a piece of information which is processed, stored or transferred by a computer. This data can be in any form such as text, images, and audio clips. Everything in a computer is data including all the software programs.
Computers work around data, and it will be useless without it. Therefore, it is important to understand the data which is the subject of this article.
History of data
‘Data’ is a Latin word and a plural of word ‘datum’. It was first used in 1640. It’s related term ‘data processing’ was first used in 1954.
Characteristics of data
In order for the data to be meaningful, it should qualify for following characteristics.
- Timeliness – Data should be available immediately when it is required.
- Accuracy – Data should be correct.
- Completeness – Data should be complete.
Type of data
Data can exist in any form such as financial data, statistical data, scientific data, or in the form of binary which is stored in the computer’s memory.
Following are some of the examples of data.
- Joee, Emith, 1234 circle, SLC, UT, 102444
- 0273 374 674 2939 4563 2237 8783 9830 7283
- 10101 11100 11100 10101 10101 1010 10101 110101 100000101
- David, Class A, Grade 8
- Michael, Director, Ministry of transport
Data versus Information
Both data and information look similar. However, In a comparison of data and information, data is a raw fact, unorganized and it doesn’t give any information to reader suppose ages, marks or grades, tracking numbers, hours and minutes. When the raw data is combined into some meaningful way, it becomes information. Suppose the average score of a class or the highest salary among employee. These all are examples of information.
Digital versus Analog Data
Digital data is represented by a series of zeros and ones e.g. 01010101010101. While analog data is represented by analog signals such as current or voltage pulse. Digital data has some discrete values and analog data is continuous in nature.
Units of data
The smallest unit of data is a bit or binary digit. It is a single value and it could be either one or zero. Nibble is another relatively larger unit of data and it consists of 4 bits.
Following are some of the units of data with their values.
How data is stored in the computer?
Everything in a computer including graphics, images, videos, sounds, text, and software programs are represented by a pattern of just two numbers. Those two numbers are called binary numbers and they are zero and one. They are further encoded and decoded when required.
Inside the computer, data is organized and manipulated in following data structures. Each data structure has specific properties, limitations, and benefits.
- Link List
In a computing context, data redundancy means the existence of the same data in two different places on the computer. Example of data redundancy would be a single file of students reside in five different places in the hard disk.
Data redundancy has the following major disadvantages,
- It wastes a lot of space
- It reduces search efficiency