63. The "strong tie" group size limit is 150 people.

63. The "strong tie" group size limit is 150 people.

64. People Are Hard-Wired for Imitation & Empathy

64. People are hard-wired for imitation and empathy.

65. Doing things together bonds people together.

65. Synchronous activities are actions you take together with others, where everyone is doing the same thing at the same time in physical proximity to one another.

66. People expect online interactions to follow social rules.

66. People expect online interactions to follow social rules

67. People like to differing degrees depending on the media.

68. Speakers' brains and listeners' brains sync up during communication.

68. Speakers' brains and listeners' brains sync up during communication.

70. Laughter bonds people together

71. People can tell when a smile is real or fake more accurately with video.

69. The Brain Responds uniquely to people you know personally.