Learning Outcomes
By the end of this lesson, learners will be able to:
- Understand the binary number system
- Convert decimal numbers to binary
- Convert binary numbers to decimal
- Perform binary arithmetic
1. Introduction to Binary Numbers
The binary number system is a base-2 numbering system used by computers.
Unlike the decimal system (base 10), binary uses only two digits:
1
Computers use binary because electronic circuits have two states:
| State | Binary Value |
|---|---|
| Off | 0 |
| On | 1 |
Every piece of data processed by a computer is represented using binary numbers.
2. Binary Place Values
Each digit in a binary number represents a power of 2.
| Power of 2 | Value |
|---|---|
| 2^0 | 1 |
| 2^1 | 2 |
| 2^2 | 4 |
| 2^3 | 8 |
| 2^4 | 16 |
| 2^5 | 32 |
Example binary number:
Represents:
3. Converting Binary to Decimal
Example:
Step-by-step conversion:
So:
4. Converting Decimal to Binary
Example: Convert 19 to binary.
Divide repeatedly by 2.
| Division | Remainder |
|---|---|
| 19 ÷ 2 = 9 | 1 |
| 9 ÷ 2 = 4 | 1 |
| 4 ÷ 2 = 2 | 0 |
| 2 ÷ 2 = 1 | 0 |
| 1 ÷ 2 = 0 | 1 |
Read remainders from bottom to top.
So:
5. Binary Addition
Binary addition follows these rules:
| Addition | Result |
|---|---|
| 0 + 0 | 0 |
| 0 + 1 | 1 |
| 1 + 0 | 1 |
| 1 + 1 | 10 |
Example:
+0101
Step-by-step result:
6. Binary Arithmetic in Computing
Binary arithmetic is used in:
- computer processors
- digital circuits
- memory storage
- programming
- encryption systems
Every operation performed by a computer is based on binary calculations.
7. Example in Programming
Binary logic is used in programming languages.
Example condition:
Binary operations are also used in:
- bitwise operations
- network protocols
- file encoding
Real-World Example
A pixel in an image is stored as binary data.
Example RGB pixel values:
| Color | Binary |
|---|---|
| Red | 11111111 |
| Green | 00000000 |
| Blue | 00000000 |
This represents a pure red pixel.
Lesson Summary
In this lesson we learned:
- Binary numbers use base 2
- Computers process information using 0 and 1
- Binary numbers can be converted to decimal
- Decimal numbers can be converted to binary
- Binary arithmetic follows simple rules