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For example, letters and characters are changed into binary using special codes like American Standard
Code for Information Interchange (ASCII). Each letter has a unique binary number that the computer
understands. Similarly, numbers, images, and sounds are also translated into binary so the computer
can store and process them.

By using binary code, computers can perform complex tasks and handle all kinds of information quickly
and accurately, even though they only understand 0s and 1s internally. This is how digital data is created,
stored, and shared in the computer world.

NUMBER SYSTEM

A number system is a systematic way of representing numbers in terms of quantities. There are a lot
of number systems in existence. Consider a digital clock. Digital clocks have 24 hours, each consisting
of 60 minutes. Each minute is in turn composed of 60 seconds. When you learnt to count, you used the
numbers, like 1, 2, 3, etc. Similarly, computers also have their own number system, known as the binary
number system.

The total number of digits used in a number system is called its base or radix. Therefore, when
someone says that they are working with a number system of radix 2, it means base 2, i.e., binary
number system. The base is written after the number as subscript such as (512) . In this example, the
10
number 10 is written as the subscript to express the number in the decimal number system.

Factbot

The numerical digits, we use today, i.e., 1, 2 and 3 are based on the Hindu-Arabic numeral system.
Different names for the number 0 include zero, nought, naught, nil, zilch and zip.

Decimal Number System

The decimal number system is a standard for denoting numbers. It consists of ten digits ranging from 0
to 9. Only these digits can be used to represent a numeric value in the decimal number system. Hence,
the base of the decimal number system is 10. The decimal number system is the most commonly used.
The value represented by an individual digit depends on the weight and position of the digit.

The first digit's position to the left of the decimal point is considered 0. The second digit's position to the
left of the decimal point is considered 1, and so on. The first digit's position to the right of the decimal
point is considered -1. The second digit's position to the right of the decimal point is considered -2, and
so on.
In a decimal number system, each digit's value is determined by multiplying the digit itself by the weight
of its position within the number, and then summing up the results. This method is known as the
expansion method. The right-most digit of the number has the lowest weight. This digit is called the
Least Significant Digit (LSD). The number's left-most digit has the highest weight. This digit is called
the Most Significant Digit (MSD). So, in the number 724, the most significant digit is 7, and the least
significant digit is 4.

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