can someone explain to me what is this "rule" I see a lot in posts titles? sometimes mixed with other words? I'm having a hard time to understand its meaning
The rule of the community is you must post before you leave after viewing something. It's obviously not anything policed.
Someone started showing their adherence to this rule by putting the word 'rule' in their post title. People continued this trend, sometimes using a play on words related to the post itself, making crap portmanteaus etc. they're usually not very cryptic.
My post got removed for having a title that claimed that rule was not in the title, despite the word, "rule" being present in the denial. This is a kangaroo court.
IIRC, 195 was an apartment number or something and some roommates made /r/195 and to shitpost in, which inexplicably became super popular. Eventually the sub got overrun by some trolls or something, so there was an exodus to /r/196.