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What is Binary?

Visual representation of binary digits with 0s and 1s
Binary uses only 0s and 1s to represent numbers

Binary is a number system that computers use to understand information. Unlike our everyday decimal system that uses 10 digits (0-9), binary uses only two digits: 0 and 1.

Each binary digit is called a "bit". Computers use binary because they have billions of tiny switches that can only be either ON (1) or OFF (0).

Binary addition works just like regular addition, but with only two digits. Learning binary helps us understand how computers process information and solve math problems.

How to Add Binary Numbers

Step-by-step visual guide showing binary addition
Visual guide to the binary addition process

Adding binary numbers is similar to adding decimal numbers. We work from right to left, column by column. Here's how:

Basic Rules

0 + 0 = 0
0 + 1 = 1
1 + 0 = 1
1 + 1 = 10

When adding two 1s, we write down 0 and carry over 1 to the next column.

Let's practice with an example:

Example: Add 101 (5 in decimal) and 110 (6 in decimal)
Step 1: Start from the right → 1 + 0 = 1
Step 2: Next column → 0 + 1 = 1
Step 3: Left column → 1 + 1 = 10 (write 0, carry 1)
Step 4: Write the carried 1 → 1011

So 101 + 110 = 1011 (which is 11 in decimal). Great job!

Binary Addition Rules

Visual representation of all binary addition rules
All possible combinations for binary addition

Here are all the rules you need to know for adding binary numbers:

First Number Second Number Carry In Result Carry Out
00000
01010
10010
11001
00110
01101
10101
11111

The most important thing to remember is that when you add two 1s, you get 0 and carry 1 to the next column. This is similar to how in decimal addition, when you add 5+5, you get 0 and carry 1 to the next column.

Solved Examples

Multiple examples of binary addition with step-by-step solutions
Step-by-step solutions for binary addition problems

Let's solve some binary addition problems together:

Example 1: Add 101 + 011

1
Write the numbers with columns aligned:
  101
+ 011
------
                
2
Right column: 1 + 1 = 10 → write 0, carry 1
  1  ← carry
  101
+ 011
------
    0
3
Middle column: 0 + 1 + carry 1 = 10 → write 0, carry 1
 11  ← carry
  101
+ 011
------
   00
4
Left column: 1 + 0 + carry 1 = 10 → write 0, carry 1
1 11  ← carry
  101
+ 011
------
  000
5
Write the final carry: 1 → 1000
  101
+ 011
------
 1000

Answer: 101 + 011 = 1000 (which is 8 in decimal)

Binary Addition Quiz

Test your binary addition skills with this 5-question quiz. Choose the correct answer for each question.

1. What is 1 + 1 in binary?
2. Add these binary numbers: 100 + 101
3. When adding 1 + 1 in binary, what do you carry to the next column?
4. What is the result of 111 + 001?
5. Which of these is correct about binary addition?

Frequently Asked Questions

Here are answers to common questions about binary addition:

Binary Trivia

Discover interesting facts about binary numbers:

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