1、通用保留关键字
break | delete | function | return | typeof |
case | do | if | switch | var |
catch | else | in | this | void |
continue | false | instanceof | throw | while |
debugger | finally | new | true | with |
default | for | null | try |
JavaScript预定义了很多全局变量和函数，应当避免把它们的名字用做变量名和函数名:
arguments | encodeURI | Infinity | Number | RegExp |
Array | encodeURIComponent | isFinite | Object | String |
Boolean | Error | isNaN | parseFloat | SyntaxError |
Date | eval | JSON | parseInt | TypeError |
decodeURI | EvalError | Math | RangeError | undefined |
decodeURIComponent | Function | NaN | ReferenceError | URIError |
2、ECMAScript 5 增加保留关键字
class | const | enum | export | extends |
import | super |
普通模式下合法，但严格模式下是保留关键字：
implements | let | private | public | yield |
interface | package | protected | static |
严格模式下做了严格限制，并不完全是保留字，但不能用作变量名，函数名或参数名：
arguments | eval |
3、ECMAScript3关键字
abstract | double | goto | native | static |
boolean | enum | implements | package | super |
byte | export | import | private | synchronized |
char | extends | int | protected | throws |
class | final | interface | public | transient |
const | float | long | short | volatile |