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Visual QuickStart Guide: JavaScript, Ninth Edition by Dori Smith, Tom Negrino

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B. JavaScript Reserved Words

Reserved words are words that have special meaning to JavaScript. Therefore, they cannot be used as variable or function names.

You’ll recognize many of the reserved words from previous chapters, but others will be unfamiliar. Some of the latter group are future reserved words; that is, it’s expected that they might be used in future editions of ECMAScript. They’re being set aside now so that you won’t have to revise your code when revisions are released.

ECMAScript Edition 3 Reserved Words

These words are part of the JavaScript language as of ES3.

break

case

catch

continue

default

delete

do

else

finally

for

function

if

in

instanceof

new

return

switch

this

throw

try

typeof

var

void

while

with

ES3 Future Reserved ...

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