Spam
From Soyjak Wiki, The Free Soycyclopedia
Spam is an act where a user or poster frequently makes multiple threads/posts for multiple reasons, which disrupts the discussion of the website/board.
Imageboards
On imageboards it is usually to fill the board with coal for the purposes of wiping the catalogue or filling a thread (usually NSFW content or mass replying), but it can also be a tactic for advertising, which is typically CP websites or other imageboards.