As a programmer, you have a lot of flexibility when naming your variables. You can be very creative in naming your variables, but you don’t want to get too crazy. Most important, your variable names should accurately describe the data that you store inside them.
Each of the following variable declarations creates a variable with a good and descriptive name. By looking at them, you can probably guess what the data stored inside them looks like.
var myFirstName; var favoriteFood; var birthday; var timeOfDay;
Notice how we separate words in variable names by using capital letters for every word after the first one. Variable names can’t contain spaces, so programmers have created several other ways to separate words. This particular style is called camelCase. Can you guess why it has that name?
After looking at these examples, what would you name variables for storing the following pieces of data?
Your pet’s name
Your favorite school subject
The age of your best friend
Your street address
In addition to the rule that variable names must not contain spaces, there are several other rules that you must follow:
Variable names must begin with a letter, an underscore (_), or a dollar sign ($).
Variable names can only contain letters, numbers, underscores, or dollar signs.
Variable names are case sensitive.
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