Tokens

Tokens form the vocabulary of the Go language. There are four classes: identifiers, keywords, operators and delimiters, and literals. White space, formed from spaces (U+0020), horizontal tabs (U+0009), carriage returns (U+000D), and newlines (U+000A), is ignored except as it separates tokens that would otherwise combine into a single token. Also, a newline or end of file may trigger the insertion of a semicolon. While breaking the input into tokens, the next token is the longest sequence of characters that form a valid token.

Tokens 是Go语言的符号表.分为五类(原文是四类，但写了五类,应该是写错了)：标识符、关键字、操作符、分界符,(http://baike.baidu.com/view/1208327.htm)(注：[字面量是指双引号引住的一系列字符](http://baike.baidu.com/view/1208327.htm),go语言则更丰富)

更多可以看看这篇问文章介绍：Go语言的标识符、关键字、字面量、类型