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= Assigns the value of the righthand operand to the variable on the
left.

Example: t o t a l = 1 0 0 ;
Example: t o t a l = ( p r i c e + t a x + s h i p p i n g ) ;
+= Adds the value of the righthand operand to the lefthand variable.
(also -=, *=, /=) Example: t o t a l + = s h i p p i n g ;
(adds value of shipping to total and assigned result to total)
&= Assigns result of (lefthand operand && righthand operand) to
(also |=) lefthand operand

Statements
Statements define the flow of a script, known as "program flow." A statement, like a fully
grammatical English sentence, is made up of smaller expressions that, altogether, evaluate
into a cogent meaning. In JavaScript, statements are organized as conditionals, loops,
object manipulations, and comments.

Good practice suggests that each JavaScript statements should be terminated with a
semicolon (;). This is often not strictly necessary, as a new line also serves to separate
statements, but when multiple statements reside on the same line the semicolon delimiter is
mandatory.

A set of statements that is surrounded by braces is called a block. Blocks of statements are
used, for example, in functions and conditionals.

y ; but this
Normally statements are executed sequentially: x = 1 ; y = 2 ; z = x +
can be altered by some statements that test a condition and branch or loop according to the
result.

Conditionals
Conditional statements direct program flow in specified directions depending upon the
outcomes of specified conditions. These tests are a major influence on the order of
execution in a program.

if...else
As seen in many programming languages, if the condition evaluates to true then the block
of statements1 is executed. Optionally, an else clause specifies a block of statements2
which are executed otherwise. You may omit the else clause if there are no statements
which need to be executed if the condition is false.
i f ( c o n d i t i o n )
{ s t a t e m e n t s 1 ; }

e l s e
{ s t a t e m e n t s 2 ; }

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