# You really don't want to learn this language

This language is written, very rarely (maybe never) spoken. In fact, it would be difficult to pronounce!

Still, it's a common language. In fact, you've probably come across it here (puzzling.SE) often!

But, hardly anybody (maybe nobody) learns this language. In fact, you wouldn't want to learn it, that defeats its purpose!

• I think you underestimate the capabilities of the brain and the determination of some people. I have seen the claim by some that they could read this language on the fly. I find the claim believable. – Ross Millikan Dec 4 '18 at 5:01
• @RossMillikan No I can believe it! My draft had 'never' and 'nobody' ... but then I thought ... better put 'very rarely' and 'hardly anybody' because there's probably That Guy ... :-) – deep thought Dec 4 '18 at 5:09
• Some of the stage calculators were reputed to know the multiplication table up to $100 \times 100$, which is a lot of facts. If you read a lot of this language you will learn the most common tens of English words by sight. You can then work out others quickly with practice. I know many of the letter correspondences but cannot form words from them easily. – Ross Millikan Dec 4 '18 at 5:19
• @RossMillikan I don't doubt that you can! But unlike 100x100, you might actually have a reason to avoid learning (or unlearn) this – deep thought Dec 4 '18 at 5:26
• @RossMillikan To be fair, there's a lot of repetition in the tables. – Don Thousand Dec 4 '18 at 13:54

I'm going to go out on a limb and say...

although not technically a "language" per se, ROT13, mainly because it fits the clues well.

This language is written, very rarely (maybe never) spoken. In fact, it would be difficult to pronounce!
rot13 is often written down, but it is never communicated verbally as it is very rare that something encoded with rot13 is remotely pronounceable.

Still, it's a common language. In fact, you've probably come across it here (puzzling.SE) often!
rot13 is commonly used for basic encryption and can be found all over puzzling.SE to encode spoilers in comments.

But, hardly anybody (maybe nobody) learns this language. In fact, learning it defeats its purpose!
No one can usually "read" rot13 simply by looking at it, they usually go through an online decoder. "Learning" to read rot13 would defeat its' main purpose, since it exists to hide spoilers.

• Well that didn't take long :-) Well done. – deep thought Dec 4 '18 at 3:07
• @deepthought I'm surprised that was right! I loved the riddle since it was nice and easy, and had a connection to PSE. – Hugh Dec 4 '18 at 4:19
• Sbe jung vg'f jbegu, vg'f abg gung uneq gb yrnea gb ernq egb13. V pna qb vg nyzbfg nf snfg nf V pna ernq Terrx be Plevyyvp yrggref. Vg qbrf fgvyy freir vgf checbfr, fvapr (rkprcg sbe n srj pbzzba cuenfrf) V fgvyy arrq gb pbapragengr gb or noyr gb ernq vg. – Ilmari Karonen Dec 4 '18 at 14:08
• @IlmariKaronen I guess the point is, you really can't read it as easily as English. – Hugh Dec 4 '18 at 14:34