A variable is something that holds values or information. The values can be numbers (numeric values), text (strings) or some other kinds of information such as dates, boolean values(true/false) and more. These values can vary from time to time, that is why the name variable. It is similar to the post boxes in the post office, the contents of the post boxes can change but the post boxes still have the same name or label.
In order to identify the variables, we have to name them. There are a few rules regarding variable names in JavaScript , as shown below:
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