No captcha?

Hello,
I am learning programming and just discovered this website. But I am curious, how does it protect its users from spammers (people who post illegal or annoying things) without a reCaptcha? I thought clicking this blue box is required to prove that you are not a robot, can you please share any javascript that you use for this purpose?
Thank you and have a nice day,
Brian

413 >>28 tightly grouped suppression posts in three days without ban

stallman spammer

counts >>8,28 | rates >>30 | 100-groups >>47,49 | hourly count chart >>53,54 | timestamp delta table >>59,60 | "die" post decorators >>82