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character.codes

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Guides and references to help you understand character encodings, HTML entities, Unicode, and more.

HTML

HTML Entities: A Complete Guide

Learn what HTML entities are, why they exist, and how to use named and numeric character references in your markup.

Unicode

Understanding Unicode: Code Points, UTF-8, and Beyond

A practical introduction to Unicode, code point notation, and the differences between UTF-8, UTF-16, and UTF-32.

ASCII

The ASCII Table: Every Character from 0 to 127

The complete ASCII character set explained — control characters, printable characters, and how they map to decimal, hex, and binary.

URL

URL Encoding Explained: When and How to Percent-Encode

Understand percent-encoding, RFC 3986 reserved characters, and the difference between encodeURI and encodeURIComponent.

Emoji

Emoji and Unicode: How Emoji Actually Work

Discover how emoji are represented as Unicode code points, how ZWJ sequences combine characters, and why emoji look different across platforms.

General

How to Type Special Characters on Any Keyboard

Learn how to type special characters on Windows, macOS, and Linux using Alt codes, Option key shortcuts, and Compose key sequences.

HTML

HTML Symbols Reference: Arrows, Math, Currency, and More

A comprehensive reference of HTML symbol entities for arrows, math operators, currency signs, and other common symbols.

Unicode

Unicode Arrows: Every Arrow Symbol with Code Points

A complete table of Unicode arrow symbols organized by direction and style, with code points and copy-paste support.

HTML

Em Dash vs. En Dash vs. Hyphen: When to Use Each

Understand the difference between em dashes, en dashes, and hyphens, with HTML entities, Unicode code points, and typing shortcuts for every OS.

Encoding

Base64 Encoding Explained: How It Works and When to Use It

Learn how Base64 encoding converts binary data to text, the 64-character alphabet, padding, and practical uses in data URIs, email, and JWTs.

General

From Morse Code to Unicode: A Brief History of Character Encoding

Trace the evolution of character encoding from telegraph codes through ASCII, code pages, and ISO 8859 to Unicode and UTF-8.

Unicode

UTF-8 vs. UTF-16: Differences, Trade-offs, and When to Use Each

A byte-level comparison of UTF-8 and UTF-16 encoding, covering surrogate pairs, BOM, size trade-offs, and real-world usage.

HTML

HTML Special Characters in Forms, URLs, and JSON

How to correctly escape special characters in HTML attributes, JavaScript strings, JSON, and URLs to prevent XSS and encoding bugs.

Unicode

Unicode Math Symbols: A Developer's Reference

A categorized reference of Unicode mathematical symbols including operators, relations, set theory, logic, Greek letters, and sub/superscripts.

Unicode

Whitespace Characters in Unicode: Spaces You Didn't Know Existed

Explore Unicode whitespace characters from non-breaking spaces to zero-width joiners, with visual comparisons and practical use cases.