This construction provides a nondisruptive way to trap for errors and handle them gracefully. Both parts of this exception-handling construction are r

The typeof operator returns one of six string descriptions of the data type of a value. Those returned types are: boolean function

Executes statements in a loop as long as a condition is true. Because the condition is tested at the beginning of the loop, it is conceivable that und

The with statement adds an object to the scope of every statement nested within. This can shorten the code of some statement groups that rely on a

Stops execution of the current function. A return statement can be located anywhere within the function, including inside control structures. You c

This is the add-by-value operator. This class of operator combines a regular assignment operator ( = ) with one of the many other operators to c

The addition operator works with both numbers and strings, but its results vary with the data types of its operands. When both operands are numbers,

The AND operator compares two Boolean expressions for equality. If both expressions evaluate to true , the result of the && operator also

Stops execution of the current loop and returns control to the next script statement following the end of the current loop.

The catch operator is described in chapter: javascript Operators try/catch

This operator is commonly used with javascript: pseudo-URLs that invoke functions. If the function returns a value, that value is ignored by the calling expression.