do...while	- the do loop iterates at least once.
	do
		statement
	while (condition)

for		- creates a loop that consists of three optional expressions, enclosed in parentheses and separated by semicolons, followed by a block of statements executed in the loop.
	for(var i = 0; i < 9; i++) {
		alert(i)
		}

for...in	- Iterates a specified variable over all the properties of an object. For each distinct property, JavaScript executes the specified statements.
	for (variable in object)
		statements
	function dump_props(obj, objName) {
		var result = ""
		for (var i in obj) {
			result += objName + "." + i + " = " + obj[i] + "<BR>"
		}
		return result
	}

function	- Declares a JavaScript function with the specified parameters. Acceptable parameters include strings, numbers, and objects.
	function name([param] [, param] [..., param]) {
		statements
	}

if...else	- Executes a set of statements if a specified condition is true. If the condition is false, another set of statements can be executed.
	if (condition)
		statements1
	[else
		statements2]

return	- Specifies the value to be returned by a function.
	function square(x) {
		return x * x
	}

switch	- Allows a program to evaluate an expression and attempt to match the expression's value to a case label.
	switch (expression) {
		case label :
			statement
			break
		case label :
			statement
			break
		...
		default :
			statement
	}

var	- Declares a variable, optionally initializing it to a value.
	var var1 = 0, var2 = 0

while	- Creates a loop that evaluates an expression, and if it is true, executes a block of statements. The loop then repeats, as long as the specified condition is true.
	while (condition) {
		statements
	}

with	- Establishes the default object for a set of statements. Within the set of statements, any property references that do not specify an object are assumed to be for the default object.
	with (object) {
		statements
	}
	var a, x, y
	var r=10
	with (Math) {
		a = PI * r * r
		x = r * cos(PI)
		y = r * sin(PI/2)
	}

delete	- Deletes an object's property or an element at a specified index in an array.
	If the delete operator succeeds, it sets the property of element to undefined; the operator always returns undefined.
	You can only use the delete operator to delete object properties and array entries. You cannot use this operator to delete objects or variables. Consequently, you can only use the third form within a with statement, to delete a property from the object.
	delete objectName.property
	delete objectName[index]

break	- Terminates the current while or for loop and transfers program control to the statement following the terminated loop.
	break
	break label	- label Identifier associated with the label of the statement.

continue		- Terminates execution of the block of statements in a while or for loop, and continues execution of the loop with the next iteration.
	continue
	continue label	- label Identifier associated with the label of the statement. 

label
	In the following example, a statement labeled checkiandj contains a statement labeled checkj.
	If continue is encountered, the program continues at the top of the checkj statement.
	Each time continue is encountered, checkj reiterates until its condition returns false.
	When false is returned, the remainder of the checkiandj statement is completed.
	checkiandj reiterates until its condition returns false.
	When false is returned, the program continues at the statement following checkiandj.
	If continue had a label of checkiandj, the program would continue at the top of the checkiandj statement.
	checkiandj :
	while (i<4) {
		document.write(i + "<br>")
		i+=1;
		checkj :
		while (j>4) {
			document.write(j + "<br>")
			j-=1
			if((j%2)==0)
				continue checkj
			document.write(j + " is odd.<br>")
		}
		document.write("i = " + i + "<br>")
		document.write("j = " + j + "<br>")
	}