Loneliness is an unpleasant emotional response to perceived or actual isolation. Loneliness is also described as social pain – a psychological mechanism that motivates individuals to seek social connections. It is often associated with a perceived lack of connection and intimacy. Loneliness overlaps and yet is distinct from solitude. Solitude is simply the state of being apart from others; not everyone who experiences solitude feels lonely. As a subjective emotion, loneliness can be felt even when a person is surrounded by other people.
The causes of loneliness are varied. Loneliness can be a result of genetic inheritance, cultural factors, a lack of meaningful relationships, a significant loss, an excessive reliance on passive technologies (notably the Internet in the 21st century), or a self-perpetuating mindset. Research has shown that loneliness is found throughout society, including among people in marriages along with other strong relationships, and those with successful careers. Most people experience loneliness at some points in their lives, and some feel it often.