📅 Date: Jan 23, 2026
🔥 Topic: Binary System & The 8-4-2-1 Rule

🤖 Why 0 and 1?

Humans use the Decimal System (Base 10) because we have 10 fingers. Computers run on electricity, which has only two states:

  • ON (1): Current is flowing.
  • OFF (0): Current is stopped.

⚡ The Power Rule (The Magic Formula)

I found a shortcut to read Binary numbers without complex math. It's called the Powers of 2 Rule. Instead of counting 1, 2, 3... we count by doubling the value from right to left.

128 64 32 16 8 4 2 1
2^7 2^6 2^5 2^4 2^3 2^2 2^1 2^0

🧠 How to find any Binary Number?

Let's say I want to write 13 in Binary.

Step 1: Look at the table above. Which numbers sum up to 13?
Answer: 8 + 4 + 1 = 13

Step 2: Put a '1' under those numbers and '0' elsewhere. 

 8   4   2   1
[1] [1] [0] [1]  ->  1101

So, 13 in Binary is 1101.

💭 Thoughts

This "8-4-2-1" trick is super fast. I don't need to divide repeatedly; I just need to see which bits act like "switches" to make the total sum.