# Hacktivateed

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## Why do humans use decimal number system?

We use decimals every day, while dealing with money, weight, length etc. Decimal numbers are used in situations where more precision is required, than the whole numbers can provide. For example, when we calculate our weight on the weighing machine, we do not always find the weight equal to a whole number on the scale.

## Why do computers use the binary system instead of the decimal system?

Computers don’t understand words or numbers the way humans do. To make sense of complicated data, your computer has to encode it in binary. Binary is a base 2 number system. Base 2 means there are only two digits—1 and 0—which correspond to the on and off states your computer can understand.

Why do some computer systems use octal or hexadecimal instead of binary?

Octal and hex use the human advantage that they can work with lots of symbols while it is still easily convertible back and forth between binary, because every hex digit represents 4 binary digits (16=24) and every octal digit represents 3 (8=23).

The main reason why we use hexadecimal numbers is because it provides a more human-friendly representation and is much easier to express binary number representations in hex than it is in any other base number system. Computers do not actually work in hex.

### Why do we use numbers?

No matter which numerical system we use, numbers are a useful language for counting, measuring and identifying. We use numbers in an unlimited range of ways: in mathematical calculations, to make phone calls and to identify our bank accounts.

What are the four rules of decimals?

You should become efficient in using the four basic operations involving decimals—addition, subtraction, multiplication, and division.

## Why do computers only understand 1 0?

The circuits in a computer’s processor are made up of billions of transistors . A transistor is a tiny switch that is activated by the electronic signals it receives. The digits 1 and 0 used in binary reflect the on and off states of a transistor. Computer programs are sets of instructions.

## Why do computers use hexadecimal?

Hexadecimal numerals are widely used by computer system designers and programmers because they provide a human-friendly representation of binary-coded values. Each hexadecimal digit represents four bits (binary digits), also known as a nibble (or nybble), which is 1/2 of a byte.

Why does octal skip 8 and 9?

The digits used are 0, 1, 2, 3, 4, 5, 6 & 7. All the other digits can be expressed using these 8 digits. You will never see 8 or 9 in any of the numbers in the octal system. This is because the total number of digits in the number system is 8.

### Why do computers use base 8?

The advantage of base 8 is that all digits are really digits: 0-7, whereas base 16 has “digits” 0-9A-F. For 8 bits of a byte base 16 (hexadecimal) is a better fit, and won. For Unix base 8 octal, often still is used for rwx bits (read, write, execute) for user, group and others; hence octal numbers like 0666 or 0777.

Why do we use binary?

Computers use binary – the digits 0 and 1 – to store data. The circuits in a computer’s processor are made up of billions of transistors . A transistor is a tiny switch that is activated by the electronic signals it receives. The digits 1 and 0 used in binary reflect the on and off states of a transistor.

## Why are octal and hexadecimal numbers used in computers?

Octal (base-8) and hexadecimal (base-16) numbers are a reasonable compromise between the binary (base-2) system computers use and decimal (base-10) system most humans use.

## Which is the most used number system after Decimal?

Apart from decimal number system, there are a lot of other number systems. We will mention just three of them as they are the most used number systems after decimal. These are: binary number system, octal number system and hexadecimal number system.