Echo chamber is a metaphorical description of a situation in which beliefs are amplified or reinforced by communication and repetition inside a closed system. By visiting an "echo chamber", people are able to seek out information which reinforces their existing views, potentially as an unconscious exercise of conformation bias. This may increase political and social polarization and extremism . The term is a metaphor based on the acoustic Echo chamber where sounds reverberate in a hollow enclosure.
Another emerging term for this echoing and homogenizing effect on the Internet within social communities is cultural tribalism.