Clacks Overhead
Clacks Overhead is a feature based on the concept of semaphore towers from the Discworld fantasy book series written by Sir Terry Pratchett, an English author and humorist.
It was devised by 
Reddit users and allows websites to broadcast a message to the world via the non-standard X-Clacks-Overhead HTTP header. This message is usually dedicated to the memory of Terry Pratchett, reading "GNU Terry Pratchett", though it can contain any text.
According to our data, Clacks Overhead is detected on 0.06% of all websites.
- 🏠 Website
- 🔗 Links
- 🔌 Add-Ons
Discworld
Chrome📊 Rankings and Market Share
- Other
- Rank: 11
- Market share: 0.07%
⚡ Sites Using Clacks Overhead
We have data on 2,127 websites that use Clacks Overhead technology. Here is a list of some of the top ranked ones.
The highest rated site using Clacks Overhead is 
stackoverflow.com.
| # | Website | Rank | Country | Language |
|---|---|---|---|---|
| 1 | stackoverflow.com |
#101 | United States | English |
| 2 | #325 | Germany | German | |
| 3 | #470 | United Kingdom | British English | |
| 4 | #585 | English | ||
| 5 | #869 | Russia | English | |
| 6 | #1,002 | English | ||
| 7 | #1,003 | United States | English | |
| 8 |  firefox.com |
#1,362 | United States | English |
| 9 | #2,168 | Netherlands | Dutch | |
| 10 |  ubuntu.com |
#2,223 | United Kingdom | English |
| 11 | #2,481 | Germany | German | |
| 12 | #2,837 | English | ||
| 13 | #2,928 | Russia | Russian | |
| 14 | #2,995 | Netherlands | Dutch | |
| 15 | #3,436 | United States | English | |
| 16 | #3,846 | Croatia | Croatian | |
| 17 | #5,488 | English | ||
| 18 | #6,504 | Malaysia | Chinese | |
| 19 |  debian.org |
#6,931 | United States | English |
| 20 | English |
📈 Usage Statistics
Most of the sites that use Clacks Overhead:
- are located in the United Kingdom
- have content in English
- use the .com domain extension
- fall into the Business category.
Most of the sites using Clacks Overhead are from the United Kingdom, the United States, and Germany.
- United Kingdom 23.3%
- United States 17.6%
- Germany 15.3%
- France 6%
- Czech Republic 4.1%
- Netherlands 4.1%
- Canada 3.4%
- Norway 2.2%
- Spain 1.9%
- Other 22.1%
Most Clacks Overhead users speak English, German, or French.
- English 74.4%
- German 8.7%
- French 3.2%
- Czech 2.8%
- Dutch 1.4%
- Spanish 1.4%
- Russian 0.9%
- Danish 0.8%
- Italian 0.7%
- Other 5.7%
Clacks Overhead technology is especially popular on .com, .org, and .de top-level domains.
- .com 37.2%
- .org 12.6%
- .de 6.7%
- .co.uk 5.7%
- .net 5.1%
- .cz 2.5%
- .org.uk 1.7%
- .nl 1.2%
- .eu 1.2%
- Other 26.1%
The primary market segments for websites utilizing Clacks Overhead include business, entertainment, and blogs and wiki.
- Business 10%
- Entertainment 10%
- Blogs/Wiki 9.2%
- Software/Hardware 7.4%
- Internet Services 7%
- Education/Reference 6.4%
- Marketing/Merchandising 5.8%
- Online Shopping 5.2%
- Games 5%
- Other 34%
🕵️ Similar Technologies
These are some of the best Clacks Overhead alternatives.
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ASP.NET MVC💬 Frequently Asked Questions
Which country uses Clacks Overhead the most?
The majority of Clacks Overhead users are from the United Kingdom.
Who uses Clacks Overhead?
According to our data, Clacks Overhead is used on thousands of sites, including such established ones as stackoverflow.com, heise.de, and
marksandspencer.com.
Do academic institutions use Clacks Overhead?
Yes. Overall, we know of 2 academic websites in the United States that use Clacks Overhead.
How does Clacks Overhead compare to the competition?
Clacks Overhead is a moderately popular other technology, ranking ahead of 6 other other technologies we track.
What are the alternatives to Clacks Overhead?
Alternatives and possible competitors to Clacks Overhead may include 
Charset, Meta Robots, and Multi-language.
🗃️ About This Data
- We evaluate the popularity of technologies based on the number of websites where we detect their usage.
- Technologies without a detectable web footprint, and those we do not track, are not reflected in the calculated market share.
- This report is based on the analysis of 3,602,133 websites.
- Statistics were last calculated on .
- For more details, see our methodology and disclaimer.