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JavaScript | Reserved Words

Last Updated : 24 Mar, 2023
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In JavaScript, you cannot use these reserved words as variable names, label names, or function names.

Reserved Words:

abstract arguments boolean break byte
case catch char const continue
debugger default delete do double
else eval false final finally
float for function goto if
implements in instanceof int interface
long native new null package
private protected public return short
static switch synchronized this throw
throws transient true try typeof
var void volatile while with

Reserved Words added in ECMAScript 5 and 6:

awaits class enum export
extends import let super

Removed Reserved Words: The following reserved words have been removed from ECMAScript 5 and 6.

abstract boolean byte char
double final float goto
int long native short
synchronized throws transient volatile

Other Reserved Words: JavaScript can be used as the programming language in many applications.

alert all anchor area anchors
assign blur button checkbox clearInterval
clearTimeout clientInformation close closed confirm
constructor crypto decodeURI decodeURIComponent defaultStatus
document  element elements embed embeds
encodeURI encodeURIComponent escape event fileUpload
focus form forms frame innerHeight
innerWidth layer link location mimeTypes
navigate navigator frames frameRate  hidden
history image images offscreenBuffering open
opener option outerWidth outerHeight packages
pageXOffset pageYOffset parent parseFloat parseInt
password pkcs11 plugin prompt propertyIsEnum
radio reset screenX screenY scroll
secure select self setInterval setTimeout
status submit taint text textarea

HTML Event Handlers: The name of all HTML event handlers  should not be used in javascript

onblur onclick onerror
onfocus onkeydown onkeypress
onkeyup  onmouseover onload
onmouseup onmousedown onsubmit

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