Talking shit is a term and type of trash-talk that refers to various types of derogatory language aimed at an individual or any type of entity, such as a group or organization. Talking shit can be used as a tactic in fighting or brawling, used to draw attention to the matter among onlookers.
Shitposting is the act of posting "content of aggressively, ironically, and trollishly poor quality" to an online forum.
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Talking shit Wikipedia(Text) CC BY-SA