Ever Wondered How Computers “Think”?
Think about this: when you press a key on your laptop, tap an app on your phone, or stream a movie — how does the machine understand what you’re asking for?
We humans speak in words, sentences, and numbers. But computers? They don’t speak English, Hindi, or Telugu (including these because I speak them too 🙂). They speak something far simpler — a language made of just two symbols: 0 and 1.
That language is called BINARY. Now, here’s the cool part: even though it looks mysterious — just a bunch of 0s and 1s — it’s not magic at all. It’s just another way to write numbers, the same way we humans write numbers in decimal (0–9).
Think of it like this: We have different human languages in the world, but the idea is the same: people are communicating. Decimal and binary are like two different languages for numbers. Decimal is for us, binary is for computers.
And just like translating between languages, we can translate between decimal and binary. That’s what this post is all about:
- What decimal really means.
- What binary is and why computers use it.
- How to convert from binary to decimal.
- How to convert from Decimal to Binary
By the end, you’ll not only understand binary but also be able to do the conversions yourself — and trust me, it’s way simpler than it looks.
What is Decimal (Base 10):
Decimal is the number system we humans use every day. It has 10 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. Once we reach 9, we carry over to the next place: 10, 11, 12, and so on. The rightmost place is worth 1, the next place to the left is worth 10, then 100, then 1000, and so forth.
This is called base 10, because it’s built on ten digits. Think of it like counting apples:
👉 1 apple, two apples, … 9 apples, and then we need another digit to say we have 10 apples.
What is Binary (Base 2)
Binary is the language of computers. It’s built on only two digits: 0 and 1, which is why it’s called Base 2. 👉 Think of it like a light switch: Instead of counting with 0–9 like us, computers count only with ONs and OFFs
- 1 = ON
- 0 = OFF
How to Read a Binary Number (Step by Step): The trick with binary is simple:
👉 Start from the rightmost digit.
👉 Each place represents a power of 2.
- The rightmost digit is always 20 = 1.
- The next digit to the left is 21 = 2.
- Then 22 =4.
- Then 23=8.
- And so on… doubling each time as you move left.
So, every digit in binary is like a “switch” controlling one of these powers of 2:
- If the digit is 1, that power is counted.
- If the digit is 0, that power is ignored.
Converting Binary to Decimal
Let’s say convert 1011 to Decimal
Step 1: Write the binary number and label each digit with its power of 2:
Binary: 1 0 1 1
Give the base Power to each digit starting from right: 23 22 21 20
Value: 8 4 2 1
Step 2: Multiply each binary digit by its corresponding base value, starting from right:
- 1×8==8
- 0×4=0
- 1×2=2
- 1×1=1
Step 3: Add them up:
👉 8 + 0 + 2 + 1 = 11
✅ So, 1011 (binary) = 11 (decimal)
Converting Decimal to Binary
To convert a decimal number into binary, the easiest way is to keep dividing by 2 and note the remainders. Let’s say convert 13 (decimal) to binary.
- Step 1: Divide 13 by 2 → 13 ÷ 2 = 6 remainder 1
- Step 2: Divide 6 by 2 → 6 ÷ 2 = 3 remainder 0
- Step 3: Divide 3 by 2 → 3 ÷ 2 = 1 remainder 1
- Step 4: Divide 1 by 2 → 1 ÷ 2 = 0 remainder 1 (stop here).At this point, we can’t divide any further because the quotient (the result of division) has reached 0.
👉 The trick: when you’re done, read the remainders backwards (from bottom to top). In this example, it is 1101
✅ So, 13 (decimal) = 1101 (binary)
Binary may look like a secret code at first glance, but now you know it’s just another way to write numbers — using powers of 2 instead of 10. Next time you see a string like 101101, you’ll know it’s not random at all — it’s just the computer’s way of counting 🙂.
👉 Interested to know how text can be converted into binary? Check out my post Binary to Text Made Easy
👉 Interested to know how Hexadecimal can be converted into binary? Check out my post Binary to Hexadecimal Made Easy