POP3
internet & telecoms specialized uk/pɒpˈθriː/ us/ˈpɑːp/
POP3协议（一种电子邮局传输协议，是从英特网服务提供商查看和收取邮件的一种方式，Post Office Protocol 3的缩写）
abbreviation for Post Office Protocol 3: a way of looking at and collecting emails from an Internet Service Provider