Why is # called the pound sign in the US?

It comes from the abbreviation lb for pound weight

Hashtag Quiz: Chris Messina and the History of the Pound Sign

One small symbol turned into a way to organize conversations and launch movements online, and this hashtag quiz traces its journey. Play an interactive set of 10 questions on Chris Messina, IRC channels, the octothorpe, pound sign origins, Twitter linking hashtags in 2009, trending topics, the Ice Bucket Challenge, MeToo, Instagram limits and dictionary recognition.

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🎯 Daily Trivia Challenge • 🧠 10 Questions • ⏱️ 150 Seconds

Question 1 / 10 Time: 150s

Proposal
Who proposed using hashtags on Twitter in 2007?
Purpose
What were hashtags first meant to do?
IRC
Which older chat system already used # for channels?
Name
What is a playful technical name for the # symbol?
Pound
Why is # called the pound sign in the US?
Link
When did Twitter start linking hashtags to search results?
Trend
What does Twitter call popular hashtags?
Challenge
Which 2014 hashtag campaign raised money for ALS research?
Movement
Which hashtag spread worldwide in 2017 to share stories of harassment?
Instagram
What is the maximum number of hashtags Instagram has allowed per post?

Explanations: answer key for all 10 questions

Q1: Who proposed using hashtags on Twitter in 2007?
Answer: Chris Messina
He tweeted the idea.
Q2: What were hashtags first meant to do?
Answer: Group related posts together
Messina called them channel tags.
Q3: Which older chat system already used # for channels?
Answer: IRC
Internet Relay Chat.
Q4: What is a playful technical name for the # symbol?
Answer: Octothorpe
It was coined at Bell Labs.
Q5: Why is # called the pound sign in the US?
Answer: It comes from the abbreviation lb for pound weight
The lb was written with a line across.
Q6: When did Twitter start linking hashtags to search results?
Answer: 2009
This made them clickable.
Q7: What does Twitter call popular hashtags?
Answer: Trending topics
They appear on lists.
Q8: Which 2014 hashtag campaign raised money for ALS research?
Answer: Ice Bucket Challenge
People poured ice water on themselves.
Q9: Which hashtag spread worldwide in 2017 to share stories of harassment?
Answer: MeToo
It became a major movement.
Q10: What is the maximum number of hashtags Instagram has allowed per post?
Answer: 30
Using fewer is often recommended.

Hashtag Quiz – Chris Messina and the History of the Pound Sign

In August 2007, Chris Messina proposed using the # symbol to group related posts on Twitter, borrowing the idea from IRC chat channels. Twitter began linking hashtags to search results in 2009, and popular tags became trending topics.

The # symbol is called the pound sign in the US, from the abbreviation lb for pound weight, and the octothorpe in telephone engineering, a name coined at Bell Labs.

Hashtags powered campaigns such as the 2014 Ice Bucket Challenge for ALS research and the MeToo movement in 2017. Instagram has allowed up to 30 hashtags per post, and dictionaries now include hashtag as a word.

What This Quiz Teaches

Tech and social media fans will enjoy these questions.

Who invented the hashtag
Where the idea came from
What the symbol is called
Which campaigns used it
How platforms use it

Did You Know?

Hashtag was added to the Oxford English Dictionary in 2014.
In music, the sharp sign looks similar but is different.
Some people say hashtags out loud as a joke.
Brands create hashtags for campaigns.
Hashtags work on many social platforms.