conventions -
noun
a way in which something is usually done

codes - 
noun
a system of words, letters, figures, or symbols used to represent others, especially for the purposes of secrecy
verb
- convert (the words of a message) into a code so as to convey a secret meaning

secrets - 
noun
- not known or seen or meant to be known by others
- something that is not properly understood; a mystery
 
confidential/classified
horror
mystery
reality/surrealism 
restricted
unrevealed
uncommunicated/unknown
off the record
not for publication/circulation
diverted
hidden/veiled
lies/propaganda

what's hidden/diverted from the public/society?
issues that are avoided and dismissed;

climate change 
the meat industry
war
social divides between classes, gender and race
depleting water, food and fuel resources