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<meta name="description" content="Variables">
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<script id="jsbin-javascript">
/* Variables
*
* 1. Definition/Function
*
* JavaScript variables are containers for storing data values.
* In order to hold things in memory during the life-cycle of a program, we can use variables.
* Variables are named identifiers that can point to the values of a particular type (e.g., a Number, String, Boolean, Array, object).
* Variables are named as such because once created, we can change their value
* and type of value.
*
*
* 2. Creating the Variable
*
* In order to create a variable, we use the keyword, var, followed by a name for our variable.
*
* 3. Declaring the Variable
*
* There are 2 phases of using variables: declaration of the variable and initialization (or assignment) of the variable.
* These unique names are called identifiers.
* Identifiers can be short names (like x and y) or more descriptive names (age, sum, totalVolume).
* The general rules for constructing names for variables (unique identifiers) are:
* Names can contain letters, digits, underscores, and dollar signs.
* Names must begin with a letter
* Names can also begin with $ and _ (but we will not use it in this tutorial)
* Names are case sensitive (y and Y are different variables)
* Reserved words (like JavaScript keywords) cannot be used as names
/*
// 1. Declaration //
var myName;
/* At the declaration phase, the varialbe myName is undefined because we have not initialized it to anything.
*/
console.log(myName); //prints ==> undefined
// 3. Initialization or Assignment //
myName = "Rachel"; //prints ==> Rachel

// 4. Re-Assignment //
/* Variables can be reassigned as exemplified below: */
var myVariable = 1;
var myVariable = true;
myVariable = "someString";
</script>


<script id="jsbin-source-javascript" type="text/javascript">/* Variables
*
* 1. Definition/Function
*
* JavaScript variables are containers for storing data values.
* In order to hold things in memory during the life-cycle of a program, we can use variables.
* Variables are named identifiers that can point to the values of a particular type (e.g., a Number, String, Boolean, Array, object).
* Variables are named as such because once created, we can change their value
* and type of value.
*
*
* 2. Creating the Variable
*
* In order to create a variable, we use the keyword, var, followed by a name for our variable.
*
* 3. Declaring the Variable
*
* There are 2 phases of using variables: declaration of the variable and initialization (or assignment) of the variable.
* These unique names are called identifiers.
* Identifiers can be short names (like x and y) or more descriptive names (age, sum, totalVolume).
* The general rules for constructing names for variables (unique identifiers) are:
* Names can contain letters, digits, underscores, and dollar signs.
* Names must begin with a letter
* Names can also begin with $ and _ (but we will not use it in this tutorial)
* Names are case sensitive (y and Y are different variables)
* Reserved words (like JavaScript keywords) cannot be used as names
/*
// 1. Declaration //
var myName;
/* At the declaration phase, the varialbe myName is undefined because we have not initialized it to anything.
*/
console.log(myName); //prints ==> undefined
// 3. Initialization or Assignment //
myName = "Rachel"; //prints ==> Rachel

// 4. Re-Assignment //
/* Variables can be reassigned as exemplified below: */
var myVariable = 1;
var myVariable = true;
myVariable = "someString";
</script></body>
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