THE BINARY SYSTEM
The language of computers, explained simply
Number Systems Explained
A number system (or numeral system) is a way of representing numbers using a set of symbols. The "base" tells you how many unique digits the system uses. Humans have invented many throughout history:
| Base | Name | Digits Used | Example | Usage |
|---|---|---|---|---|
| 1 | Unary | | (tally marks) | ||||| = 5 | Tallying, counting |
| 2 | Binary | 0, 1 | 1010 = 10 | Computers, digital electronics |
| 3 | Ternary | 0, 1, 2 | 101 = 10 | Some experimental computers, balanced ternary |
| 4 | Quaternary | 0, 1, 2, 3 | 22 = 10 | DNA encoding (A, T, G, C) |
| 5 | Quinary | 0, 1, 2, 3, 4 | 20 = 10 | Hand counting, some ancient cultures |
| 6 | Senary | 0, 1, 2, 3, 4, 5 | 14 = 10 | Dice, some games |
| 7 | Septenary | 0-6 | 13 = 10 | Days of the week |
| 8 | Octal | 0-7 | 12 = 10 | Unix file permissions, early computing |
| 9 | Nonary | 0-8 | 11 = 10 | Rarely used |
| 10 | Decimal | 0-9 | 10 = 10 | Human standard (10 fingers) |
| 11 | Undecimal | 0-9, A | A = 10 | Rarely used |
| 12 | Duodecimal (Dozenal) | 0-9, A, B | A = 10 | Time (12 hours), inches, dozens |
| 16 | Hexadecimal | 0-9, A-F | A = 10 | Computing, colors (#FF0000), memory addresses |
| 20 | Vigesimal | 0-19 | 10 = 20 | Mayan numerals, French (quatre-vingts = 80) |
| 60 | Sexagesimal | 0-59 | 10 = 60 | Time (60 min/sec), angles (360°), Babylonian |
| 64 | Base64 | A-Z, a-z, 0-9, +, / | QmFzZS0y | Email attachments, data encoding |
Why So Many Systems?
Different bases emerged for practical reasons:
Base-10 (Decimal)
We have 10 fingers - the most natural counting system for humans. Nearly all modern cultures adopted it.
Base-12 (Dozenal)
12 is divisible by 2, 3, 4, and 6, making fractions easier. Used for time, inches, and dozens.
Base-60 (Sexagesimal)
Babylonians chose 60 because it's divisible by 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, and 30. We still use it for time and angles.
Base-2 (Binary)
Electronic circuits naturally have two states: ON/OFF. Binary is ideal for computers, not humans.
The Highest Bases
Mathematically, there's no upper limit to number bases. However, practical usage drops off after base-64:
- Base-85 (Ascii85) - Used in PDF files and Adobe PostScript for efficient binary-to-text encoding
- Base-256 - Each byte is a "digit" - used internally in some computing contexts
- Base-65536 - Theoretical; each Unicode character could be a digit
The higher the base, the more symbols you need to memorize, which is why humans settled on base-10 while computers prefer base-2.
Visual Binary Display
Below is "BASE-2" represented in binary using a retro vacuum bulb display. Each lit bulb represents a 1 (ON), and each dark bulb represents a 0 (OFF).
Binary ON (1)
When a bulb glows, it represents the binary digit 1 - electricity is flowing, the switch is ON.
Binary OFF (0)
A dark bulb represents 0 - no electricity flows, the switch is OFF. Just two states: that's all a computer needs.
8 Bits = 1 Byte
Each character is encoded in 8 bits (1 byte). "BASE-2" uses 48 bits total - 6 characters x 8 bits each.
How Binary Works
We humans use the decimal system (base-10) with digits 0-9. Computers use the binary system (base-2) with only two digits: 0 and 1. Why? Because electronic circuits have two natural states: ON and OFF.
Place Values: The Key to Understanding
Just like decimal has place values (ones, tens, hundreds), binary has place values too - but they're powers of 2 instead of powers of 10:
| Position | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|---|---|---|---|---|---|---|---|---|
| Power of 2 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 |
| Value | 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
Example: Converting Binary to Decimal
Let's convert 01001010 to decimal:
| Value | 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
|---|---|---|---|---|---|---|---|---|
| Binary | 0 | 1 | 0 | 0 | 1 | 0 | 1 | 0 |
| Calculation | 0 | 64 | 0 | 0 | 8 | 0 | 2 | 0 |
Result: 64 + 8 + 2 = 74 (which is the ASCII code for the letter "J")
Why Do Computers Use Binary?
Click any card below to explore the topic in depth:
Electrical Simplicity
Transistors (the building blocks of processors) work like tiny switches - they're either ON or OFF. This maps perfectly to 1 and 0.
Learn more →Noise Resistance
With only two states, computers can easily distinguish between signals even with electrical interference. More states would mean more errors.
Learn more →Boolean Logic
All computer operations (AND, OR, NOT) work naturally with binary values, enabling complex calculations from simple yes/no decisions.
Learn more →Scalability
Adding more bits exponentially increases capacity. 8 bits = 256 values, 16 bits = 65,536, 32 bits = 4+ billion possibilities.
Learn more →Master Binary: Deep Dive Topics
Ready to go deeper? Explore our comprehensive guides covering every aspect of binary computing:
Binary Arithmetic
Master addition, subtraction, multiplication, and division in base-2. Extensive examples, overflow handling, and hardware implementation.
45 min read →Signed Numbers & Negatives
How computers represent negative numbers. Sign-magnitude, one's complement, and two's complement explained in depth.
40 min read →Hexadecimal & Octal
The programmer's shorthand for binary. Color codes, memory addresses, file signatures, and Unix permissions.
35 min read →Data Representation
How computers encode text, images, audio, and video as binary. ASCII, Unicode, IEEE 754 floats, and more.
50 min read →Conversion Mastery
Every method for converting between number systems. Mental math tricks, algorithms, and quick reference tables.
30 min read →Binary in the Real World
Practical applications in networking, graphics, security, embedded systems, and everyday devices.
35 min read →Interactive Converter
Try converting between different number systems:
Interactive Tools
Test your skills and explore binary data with these interactive tools:
Binary Quiz
Test your binary conversion skills! Answer 10 questions and see your score.
ASCII Reference Table
Look up any character's binary, decimal, and hexadecimal values.
Common ASCII Characters
| Char | Dec | Binary | Hex |
|---|
Bit Manipulator
Click individual bits to toggle them and see the value change in real-time.
History of Binary Computing
The journey from mathematical concept to the digital age:
Practice Exercises
Test your understanding with these exercises:
1010 to decimal.
11111111 to decimal.
42 to binary.
Frequently Asked Questions
Common questions about binary and the base-2 number system:
Binary is a number system that uses only two digits: 0 and 1. It's called "base-2" because it has two possible values for each digit position. Computers use binary because electronic circuits have two natural states: ON (1) and OFF (0). Every number, letter, image, and sound in your computer is ultimately represented as a sequence of 0s and 1s.
Computers use binary because electronic components like transistors work as tiny switches that are either ON or OFF. This two-state system maps perfectly to binary's 0 and 1. Binary is also more reliable than systems with more states because it's easier to distinguish between just two voltage levels, making computers resistant to electrical noise and interference.
To convert binary to decimal, multiply each binary digit by its place value (powers of 2) and add the results. From right to left, place values are 1, 2, 4, 8, 16, 32, 64, 128, etc. For example, binary 1010 = (1×8) + (0×4) + (1×2) + (0×1) = 8 + 0 + 2 + 0 = 10 in decimal.
A bit (binary digit) is the smallest unit of data in computing, representing either 0 or 1. A byte is a group of 8 bits, which can represent 256 different values (28 = 256). Bytes are commonly used to represent characters - for example, the letter 'A' is stored as the byte 01000001 in ASCII encoding.
To convert decimal to binary, repeatedly divide the number by 2 and record the remainders. Read the remainders from bottom to top to get the binary number. For example, to convert 13: 13÷2=6 remainder 1, 6÷2=3 remainder 0, 3÷2=1 remainder 1, 1÷2=0 remainder 1. Reading remainders bottom-to-top: 1101. So 13 in decimal = 1101 in binary.
Boolean logic is a branch of mathematics dealing with true/false values, invented by George Boole in 1847. It maps directly to binary where 1 represents TRUE and 0 represents FALSE. Basic Boolean operations include AND (both must be 1), OR (at least one must be 1), and NOT (inverts the value). All computer operations are built from these simple Boolean gates.
Hexadecimal (base-16) uses digits 0-9 and letters A-F, where A=10, B=11, through F=15. It's popular in computing because each hex digit represents exactly 4 binary bits, making it a compact way to write binary. For example, the binary number 11111111 can be written as FF in hex. You'll see hex in color codes (#FF0000 for red), memory addresses, and file data.
The number of possible values with N bits is 2N (2 to the power of N). With 1 bit: 2 values (0,1). With 4 bits: 16 values (0-15). With 8 bits (1 byte): 256 values (0-255). With 16 bits: 65,536 values. With 32 bits: over 4 billion values. This exponential growth is why adding more bits dramatically increases computing capacity.
Why We're Called Base-2
"In computing, Base-2 is the foundation of everything - the binary system where all complex operations begin with simple 1s and 0s. That's our philosophy: we build from solid foundations, creating web solutions and custom applications that scale with your business. No bloat, no unnecessary complexity - just clean, efficient code that works."
Whether you're a small business looking to establish your online presence or an enterprise needing custom application development, we deliver solutions built on fundamentals that last.
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