- 行分隔符：一行就是一个语句；多个语句放一行需要手动加
;，但是不建议
- 注释不被编译，但是建议每个包一个注释
- 标识符：用于命名变量、类型等程序实体，以字母或下划线开头
- 关键字，25 个
- break, case, chan, const, continue
- default, defer, else, fallthrough, for
- func, go, goto, if, import
- interface, map, package, range, return
- select, struct, switch, type, var
- 预定义标识符，36 个
- append, bool, byte, cap, close, complex
- complex64, complex128, copy, false, float32, float64
- imag, int, int8, int16, int32, int64
- iota, len, make, new, nil, panic
- print, println, real, recover, string, true
- uint, uint8, uint16, uint32, unit64
- 空格：变量声明需要空格隔开；适当空格增加易阅读性