4chan (https://4chan.org/) is the most famous image board. As most image boards, 4chan has a nice, oldschool minimalist look, even though it contains shitty captchas for posting and the site's code is proprietary. The site tolerates a great amount of free speech up to the point of being regularly labeled "right-wing extremist site" (although bans for stupid reasons such as harmless pedo jokes are very common, speaking from experience). Being a "rightist paradise" it is commonly seen as a rival to reddit, aka the pseudoleftist paradise -- both forums hate each other to death. The discussion style is pretty nice, there are many nice stories and memes (e.g. the famous greentext stories) coming from 4chan but it can also be a hugely depressing place just due to the shear number of retards with incorrect opinions.
The site consists of multiple boards, each with given discussion topic and rules. The most (in)famous board is random AKA /b/ which is just a shitton of meme shitposting, porn, toxicity, fun, trolling and retardedness.
For us the most important part of 4chan is the technology board known as /g/ (for technoloGEE). Browsing /g/ can bring all kinds of emotion, it's a place of relative freedom and somewhat beautiful chaos where all people from absolute retards to geniuses argue about important and unimportant things, brands, tech news and memes, and constantly advise each other to kill themselves. Sometimes the place is pretty toxic and not good for mental health, actually it is more of a rule than an exception.
As of 2022 /g/ became unreadable, ABANDON SHIP. The board became flooded with capitalists, cryptofascists, proprietary shills, productivity freaks and other uber retards, it's really not worth reading anymore. You can still read good old threads on archives such as https://desuarchive.org/g/page/280004/.
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