The Brief: Redpill or Redpilling (also written as "The Red Pill,") is a term and community primarily composed of males focused on dating women in the 21st Century, but their methods often involve manipulation.

DEEP DIVE
Redpill or Redpilling (also written as “The Red Pill,”) is a term and community (largely focused on Reddit) which is primarily composed of males from their older teens to their thirties, as well as numerous outliers. Their focus is on attempting to date women in the 21st Century, and also men’s rights. However often their ideology becomes highly toxic, and focuses on teaching men how to emotionally manipulate potential partners.
The term derives from the “red pill and blue pill situation” in the film The Matrix, where Morpheus (played by Lawrence Fishburne) offers protagonist Neo (played by Keanu Reeves) a chance between a blue pill, which represents blissful ignorance, and a red pill, which represents “The truth. Nothing more,” according to Morpheus. Not every usage of “Red Pill/Blue Pill” refers to the men’s rights movement. Sometimes it is more of a general reference to the concept from the film.
Other aspects of the Red Pill Movement include a sense of “rugged individualism,” that Western Civilization has failed modern men and women but mostly men, and that a return to traditional gender roles could solve problems.