Actionscript 3.0 Fundamentals

Statements end with a ;

Variables
var name:type;

You can leave off a type, but then Flash doesn't know what type of data you are using.
Why is it benificial to list the data type?

Primative Data types:
String            A single character, or a sequence of characters
Boolean         true or false values
int                  Positive and negative whole numbers
uint                Positive whole numbers
Number         Positive and negative whole and real (i.e. fractional, like 3.5) numbers.

Constants:
const DAYS_PER_WEEK:uint = 7;

Order of Operations

1. Parentheses
2. Exponents - Math.pow(variable, exponent)
3. Multiplication and Division
4. Addition and Subtraction

Unary Operations:
!      logical negation
-      negative
+     positive
++   increment
--     decrement

Arrays:
var myArray:Array = new Array();
var myArray:Array = new Array(5);

Passing something other than a number, or more than one value, will be treated as values in the array.
var people:Array = new Array("Larry");
var players:Array = new Array(23,34,10);

Array literal, a comma separated list of values enclosed in square brackets:
var people:Array = ["Lawrence", "Herbert", "Shirley"];
trace (people);
// Size of the array.
trace(people.length);
// First element
trace(people[0]);

You can add values to the array by using it's subscript or via the push command:
people[3] = "Perry";
// Add to the end of the array.
people.push("Fay");
trace(people);
My array has now:
Lawrence, Herbert, Shirley,Perry, Fay
delete people[2];
Lawrence, Herbert, ,Perry, Fay
There is an empty values where "Shirley" was.
splice will remove a value.
var people:Array = ["Lawrence", "Herbert", "Shirley"];
// Start at position 0 and remove 1 element.
people.splice(0,1);
trace(people);
Herbert,Shirley

Decisions:
Similar to C using if-else
==   is equal to
!=    is not equal to
<     is less than
>     is greater than
<=   is less than or equal to
>=   is greater than or equal to

Boolean Operators
&&     AND
||         OR

Loops:
Again, similar to C:
while, do-while, and for loops

var i:uint = 1;
while(i<=100) {
    trace(i);
    i++;
}

var i:uint = 1;
do{
    trace(i);
    i++;
} while(i<=100)

postfix++
++prefix

for(var i:uint=1; i<=100; i++) {
    trace(i);
}

Functions:
function name(parameters):returnType {
    statements;
}

function countTo(max:uint):void {
    for(var i:uint = 1; i<=max; i++) {
          trace(i);
    }  
}

countTo(5);
countTo(10);

// You can specify defaults. Such as min has a default of 1.
function countTo(max:uint, min:uint = 1):void {
    for(var i:uint = min; i<=max; i++) {
          trace(i);
    }  
}

countTo(10);
// Here the min value is set to 5.
countTo(10,5);

Multiple variables:
function sum(...operands):Number {
    var numOperands:uint = operands.length;
    var total:Number = 0;

    for (var i:uint = 0; i < numOperands; i++) {
          total += operands[i];
    }

    return total;
}

trace (sum(1,2,3));
trace (sum(5,10));

Passing values and references
Primitive data types are passed by value (Numbers, Strings, Ints, etc). Complex (such as Arrays) are passed by reference.

Scope of variables (global, local).

Comments:
//
/* */

Use commenting skills that you learned in 1.5 and 15 for function (parameters, return values, explaination of the function).