这两年社交网站真的很火，好多上班族到办公室的第一件事就是上社交网站看好友们的动态。这里的好友不一定就是自己认识的朋友，也可能是朋友的朋友。这样一来，这个朋友圈子可就大了。原本根本不可能认识的两个人也有可能通过七回八转的朋友关系搭上线。这就是网络世界的“小世界效应”，也叫“六度分隔理论”，你听说过么？

Six degrees of separation (also referred to as the "Human Web") refers to the idea that, if a person is one step away from each person they know and two steps away from each person who is known by one of the people they know, then everyone is at most six steps away from any other person on Earth.

六度分隔理论（也叫“人网”）指的是这样一个概念，假如每个人跟自己认识的人之间是一步的距离，跟自己不认识而身边有人认识的人之间是两步的距离，那么地球上任何两个陌生人之间的距离最多也就六步之遥。

American playwright, John Guare, wrote a play in 1990, and later released a film in 1993 that popularized the term. It is Guare's most widely-known work. The play ruminates upon the idea that any two individuals are connected by at most five others.

美国剧作家约翰• 桂尔1990年创作了一部戏剧，之后在1993年出品了一部同名电影（《六度分离》），使得“六度分隔”这个说法得以普及。这部作品桂尔最广为人知的一部作品。这部剧反复传递了一个思想：任何两个人之间最多通过5个人就可以建立联系。