Notpron (also not pr0n) is an online puzzle which was launched in July 2004 by David Münnich of Saarbrücken, Germany. The front page names the puzzle as "The Hardest Riddle on the Internet", which many claim is true. The puzzle has a linear format, requiring players to solve each level in turn before progressing to the next. Many of these levels require a high level of attention and imagination to find the correct solutions.
To date, Notpron has had over 15.5 million visitors, but only 27[1] of them have been able to solve all 140 levels. This could be because the final level, "Level Nu," requires the player to use the controversial technique of remote viewing in order to find the answer.
The list of Notpron solvers is as follows: 1. Jenn Rothwell, 2. ?, 3. Shenmue, 4. Erick Nefcy, 5. Caym, 6. Ryoga, 7. ?, 8. Mehtbh, 9. Mil79, 10. Ak-01, 11. AgentBreschnew, 12. Cowley, 13. Gamemastertips, 14. Simon Jungbeck, 15. Kasper Otten, 16. Casper Putz, 17. Carolyn, 18. Komanda Zolokisevich, 19. Zorkion, 20. Marcus, 21. Luca Kabbe, 22. Zhongxia Yan, 23. Anne, 24. Raphael, 25. Reto, 26. Alex Chen, and 27. Grant Faber.[2] All names of solvers can be confirmed via e-mail at http://notpron.com/, so as to prevent any cheating.
While some say remote viewing is fake, the truth stands that the level has indeed been completed by over 2 dozen people. The answer to Level Nu has also been changed by its creator each time it is beaten, making it impossible for someone who has completed the level to give away the answer to another person. Before the last level (Level Nu) was added in August 2008, the riddle had been solved by 168 people.[3] Spiegel Online in January 2006 described the game as one of the hardest riddles on the internet and great role model for websites such as Frvade.[4] As one of the earliest, best known and most played online puzzles of its type, it has been cited as an inspiration by creators of other puzzles in the genre. It is also notable that Notpron is offered not just in English, but also in German and Mandarin Chinese.
The name is composed of the English word not and the word pron or pr0n, which is internet slang for porn, a shortened form of pornography. Thus, the name means Not Pornography or Not Pornographic. This name is derived from the earlier online puzzle, thisisnotporn.com (now offline), which inspired Münnich to create his own puzzle.[5]
Initially, the puzzle consisted of 5 levels. During the year came an addition of about 2 to 3 new levels each week. In July 2005, the developer ceased extending the game. The number of levels totaled 139 at that point. One additional level was released in late August 2008, reaching the current total of 140 levels. In May 2006, Münnich produced a certificate[6] for those who have completely solved the riddle. This certificate acknowledges one's knowledge of audio and image editing, HTML development, computers, musical understanding, persistence, logic skills, and remote viewing.
The game can present problems to some browsers such as Opera and Safari, as sound and graphics may be interpreted only in part. Therefore, the use of Microsoft's Internet Explorer is recommended. For higher levels, additional programs such as audio and graphics software may also be required. It is possible to solve the entire riddle using only free software, although to get to the final set of levels a donation of one euro or equivalent is required.
