Computers cannot understand letters or symbols directly. Instead, they use a system where every character is represented by a specific number.

Computers See Numbers

ASCII was the first major system for text, but it only included enough numbers for English letters, common digits, and basic punctuation.

The Early English Standard

Before a universal system existed, different countries used their own numbering lists. This often caused text to look like gibberish when shared between different regions.

The Language Problem

Unicode is a global standard that acts like a massive library. It assigns a unique number to every character from every language in the world.

The Universal Text Library

Every letter or symbol in Unicode has a specific 'code point.' You can think of this as a permanent personal ID number that never changes.

Unique Character IDs

A character is the abstract idea of a letter, while a 'glyph' is the actual design you see. One character can look different depending on the font used.

Ideas vs. Visual Shapes

UTF-8 is the most popular way to save text today. It is a smart system that allows computers to read and write text quickly and reliably.

Efficient Text Storage

Modern systems use 'variable-width' storage. This means common letters use very little memory, while rare symbols or emojis take up more space as needed.

Smart Sizing for Text

Systems like UTF-16 and UTF-32 are different ways to organize text numbers. They are sometimes used in specific apps or operating systems to make processing faster.

Alternative Storage Methods

Emojis are treated exactly like regular letters by computers. Each emoji, like a smiley face or a heart, has its own unique number in the Unicode library.

Pictures as Text

Some characters are created by stacking symbols. For example, an accent mark can be added to a base letter using a special 'combining' number.

Building Accented Letters

When you see weird symbols like '', it means the computer is using the wrong dictionary to translate numbers back into letters.

Handling Broken Text

A 'Byte Order Mark' is an invisible signal at the very beginning of a file. It tells the computer exactly which encoding system was used to save the text.

Hidden Text Labels

Beyond visible letters, computers use special numbers to represent invisible actions. These include starting a new line or moving text to the next tab space.

Hidden Formatting Marks

Web browsers look for a specific 'charset' tag to know which language system to use. This ensures that text from around the world displays correctly on your screen.

Unicode & Character Encodings Concepts