A keyword is a reserved word which has a special meaning in JavaScript. See also word operators if this page fails to list the word which you are interested in.
break[]
Used to exit loops, switch...case statements and labeled block statements.
case[]
Necessarily organizes switch...case statements. (It can technically be omitted, but this renders the entire statement useless.)
catch[]
Necessarily extends try...catch statements to handle errors.
continue[]
Exits single iterations of loops.
default[]
Further organizes switch...case statements.
do[]
Begins do...while loops.
else[]
Optionally extends if statements.
false[]
A Boolean constant which represents falsehood.
finally[]
Optionally extends try...catch statements to execute commands regardless of whether any error was thrown in the try block and whether any errors remained uncaught.
for[]
Begins for loops.
goto[]
Enters labeled blocks from anywhere.
if[]
Begins if statements.
return[]
Used within functions to exit the function and set the value of the function call.
switch[]
Begins switch...case statements.
this[]
An immutable variable used inside methods to reference the owning objects. See this (computer science).
true[]
A Boolean constant which represents truth.
try[]
Begins try...catch statements.
var[]
Declares a variable in anticipation of its use to prevent certain scoping issues involving functions.
var x;
x is undefined.
while[]
Begins while loops and ends do...while loops.
with[]
Begins with statements.