Naming Variables

• Remember that we declare a new variable by typing the let keyword and then assigning a name to the variable.
• A variable’s name is also known as an identifier.

let blank;

Rule 1

• Names must begin with a letter, an underscore, or a dollar sign $ (best coding practice starts names with a lowercase letter).
• The letter of the first word in an identifier should always be lowercase, and the first word of any proceeding words should be uppercase.

// This practice is called camelcase. Ex: 
// myVariable, placeHolder, camelCase

CamelCase?

Rule 2

• Names are case sensitive. If you declare a variable with the identifier myVariable, it cannot be accessed by saying myvariable or myVARIABLE

Rule 3

• Reserved words cannot be used as names.
• There are a few words used in JS that perform specific actions, such as the let keyword that tells the computer we are declaring a new variable
• Reserved words include JavaScript keywords, and all of the words included here: http://www.javascripter.net/faq/reserved.htm

Reserved words example

            let monthlyRent = 600;
            let carNote$ = 300;
            let home_address = "789 Super Fun Ln.";
            let businessAddress2 = "326 City Rd.";
            let lunchTotal$ = 11.49;

• notice the different types of data assigned
  

Exercise

• Declare new variables and convert the following phrases to an appropriate variable name, using camelCasing and other naming conventions:

1. annual income
2. bills to be paid
3. number of vacation days left
4. week one
5. week two
6. week six