All Javascript Reserved Keywords
The below list cannot be used as variable names, as they are reserved keywords. Most of them have current functionality in Javascript. Some do not, but they are words which may have some sort of functionality in the future. Avoid using these words in variable names.

1.abstract
2.argument
3.await
4.boolean
5.break
6.byte
7.case
8.catch
9.char
10.class*
11.const*
12.continue
13.debugger
14.default
15.delete
16.do
17.double
18.else
19.enum*
20.eval
21.export*
22.extends*
23.false
24.final
25.finally
26.float
27.for
28.function
29.got
30.if
31.implements
32.import*
33.in
34.instanceof
35.int
36.interface
37.let*
38.long
39.native
40.new
41.null
42.package
43.private
44.protected
45.public
46.return
47.short
48.static
49.super*
50.switch
51.synchronized
52.this
53.throw
54.throws
55.transient
56.true
57.try
58.typeof
59.var
60.void
61.volatile
62.while
63.with
64.Yield