When you send a message, browse the web, or save a photo to your computer, have you ever wondered: how does the computer actually "understand" these actions? In fact, no matter how complex it appears, all data that a computer processes is ultimately represented by just two simple numbers: 0 and 1.

This is the binary system – the fundamental language that all electronic devices "speak" and "understand."

In this article, we will explore:

  • What is the binary system?
  • Why is it so important?
  • The advantages and disadvantages of the binary system.
  • Applications of the binary system in real life.
  • How to decode binary strings into understandable numbers and characters, with concrete examples.

Let's dive in!

1. What is the Binary System?

The binary system (Binary Number System) is a numerical system that uses only two digits: 0 and 1. Each digit in binary is called a bit (binary digit).

In computer science, binary is essential because computers operate using electrical signals that have two states: ON (1) and OFF (0).

Example of binary numbers:

1011, 110010, 00101101

2. Why is Decoding the Binary System Necessary?

  • To understand how computers store and process data.
  • To convert machine-readable binary data into human-readable formats (such as decimal numbers or text).
  • To program and manipulate data at the bit level in fields like security, compression, and hardware design.

3. Advantages and Disadvantages of the Binary System

Advantages

  • Simple and easy to design for electronic devices.
  • Less prone to errors due to only two states (on/off).
  • High error tolerance in communication and storage.

Disadvantages

  • Representing large numbers can result in long and difficult-to-read sequences.
  • Direct manipulation with binary is very inconvenient for humans.

4. Applications of the Binary System in Real Life

  • Computer Processing: All CPUs, RAMs, hard drives, and communication networks are based on binary.
  • Telecommunications: Data transmission via electrical signals, fiber optics.
  • Encryption and Security: Data encryption, bit manipulation in blockchain, SSL/TLS protocols.
  • Device Control: From LED lights to self-driving cars and drones.

5. How to Decode Binary into Decimal

To convert binary to decimal:

  • Write down the binary number.
  • Assign powers of 2 to each bit, starting from the right (0 power).
  • Sum the values of the bits that are set to 1.

General formula:

Example: Convert 1011 to decimal

1 × 2³ + 0 × 2² + 1 × 2¹ + 1 × 2⁰ = 8 + 0 + 2 + 1 = 11

Result: 1011 (binary) = 11 (decimal)

6. How to Decode Binary into Characters (ASCII)

In computers, characters are encoded using the ASCII (American Standard Code for Information Interchange) system. Each character corresponds to an 8-bit binary code.

Steps to decode:

  1. Group binary into sets of 8 bits.
  2. Convert each group from binary to decimal.
  3. Look up the ASCII table to find the corresponding character.

Example:

01001000 01101001
→ 01001000 = 72 → 'H'
→ 01101001 = 105 → 'i'
Result: "Hi"

7. Practical Examples

Example 1: Convert 110010 to decimal

1 × 2⁵ + 1 × 2⁴ + 0 × 2³ + 0 × 2² + 1 × 2¹ + 0 × 2⁰ = 50

Example 2: Decode 01000001

  • 01000001 → 65 (decimal)
  • 65 in ASCII → A

Result: A

8. Notes When Working with Binary

  • Bit is the smallest unit.
  • Byte = 8 bits.
  • Other commonly used systems:
    • Decimal system (base 10)
    • Hexadecimal system (base 16)
  • Tools like Windows Calculator (Programmer mode) or online converters can help with binary calculations.

9. Basic ASCII Table

DecBinaryCharacter
3200100000(Space - dấu cách)
3300100001!
3400100010"
3500100011#
3600100100$
3700100101%
3800100110&
3900100111'
4000101000(
4100101001)
4200101010*
4300101011+
4400101100,
4500101101-
4600101110.
4700101111/
48001100000
49001100011
50001100102
51001100113
52001101004
53001101015
54001101106
55001101117
56001110008
57001110019
6501000001A
6601000010B
6701000011C
6801000100D
6901000101E
7001000110F
7101000111G
7201001000H
7301001001I
7401001010J
7501001011K
7601001100L
7701001101M
7801001110N
7901001111O
8001010000P
8101010001Q
8201010010R
8301010011S
8401010100T
8501010101U
8601010110V
8701010111W
8801011000X
8901011001Y
9001011010Z
9701100001a
9801100010b
9901100011c
10001100100d
10101100101e
10201100110f
10301100111g
10401101000h
10501101001i
10601101010j
10701101011k
10801101100l
10901101101m
11001101110n
11101101111o
11201110000p
11301110001q
11401110010r
11501110011s
11601110100t
11701110101u
11801110110v
11901110111w
12001111000x
12101111001y
12201111010z

👉 Note: Codes from 0-31 are control characters and are not displayed as letters.

10. Flowchart Illustration: Binary Decoding Process

Flowchart:

[Step 1] Receive binary string
        ↓
[Step 2] Group into sets of 8 bits
        ↓
[Step 3] Convert binary to decimal
        ↓
[Step 4] Lookup ASCII table
        ↓
[Step 5] Combine into readable text

Conclusion

The binary system is the "native language" of computers. Understanding how to decode binary helps you:

  • Understand how computers store and process data.
  • Efficiently tackle low-level programming tasks.

Wishing you clear understanding and proficiency in working with binary-related topics!