#
Hash symbol
The hash symbol (#) has evolved from a simple number sign to the cornerstone of social media communication through hashtags, while maintaining critical functions in programming, telecommunications, and data organization.
Technical Details
- ASCII Code
- 35
- HTML Entity
- #
- Hexadecimal
- 0x23
- Binary
- 00100011
- Octal
- 43
Usage & Examples
Programming
char symbol = '#'; // ASCII 35HTML/Web
# or #Common Uses
How to Type This Character
Windows
Mac
💡 Pro tip: The fastest way is to bookmark this page or copy the character from our ASCII library!
Related Characters
About the Hash symbol
Social Media Revolution
The # symbol transformed digital communication by creating hashtags, enabling content categorization, trend tracking, and community building across platforms like Twitter, Instagram, and TikTok. It revolutionized how information spreads and conversations organize online.
Programming Fundamentals
Essential in programming languages for comments (Python, Bash), preprocessor directives (C, C++), and special syntax markers. The symbol helps structure code, documentation, and system configurations across software development.
Telecommunications Infrastructure
Critical for phone systems as the 'pound key' or 'hash key' on keypads, enabling menu navigation, automated system interactions, and feature activation in telephony and interactive voice response systems.
Data Organization
Used for indexing, numbering systems, and data structuring in databases, spreadsheets, and content management. The symbol provides visual hierarchy and reference systems in digital and print media.
History of the Hash symbol
Commercial Origins
The symbol emerged in commercial contexts as an abbreviation for 'number' (from Latin 'numero'), appearing in invoices, ledgers, and business correspondence to denote quantities and reference numbers.
Touch-Tone Phones
Bell System included the # symbol on push-button telephone keypads, establishing its role in telecommunications and creating the foundation for interactive phone systems.
Computer Programming
Early programming languages adopted # for various syntactic purposes, including comments and preprocessor directives, establishing its technical significance in software development.
Twitter Hashtags
Chris Messina proposed using # to group related tweets, creating the hashtag concept that would transform social media communication and content discovery worldwide.
Global Hashtag Culture
Hashtags became universal across social platforms, enabling social movements (#MeToo, #BlackLivesMatter), marketing campaigns, and cultural phenomena, making # a symbol of digital activism and communication.
Cultural Impact
The hash symbol evolved from mundane commercial notation to a powerful tool for social organization and digital expression, enabling grassroots movements, cultural trends, and new forms of human connection in the digital age.
Usage Examples
Social Media
ExampleContent categorization and trend participation
Programming
ExampleCode documentation and compiler directives
Phone Systems
ExampleInteractive voice response and menu navigation
Document Organization
ExampleNumbering systems and reference identification