called age. With the above command, computer will reserve some memory and allow you to store to or retrieve from that memory with the name you chose, age. Remember at this point our variable age is null or has a garbage valuewhatever computer's memory slot happens to hold.
You can declare more than one variable by separating each with a comma and still use one var command, as:
var state, city, zip, country;
Also, keep your variable names meaningful. Avoid using a variable name such as k, l, m, z, or a because you may have hard time figuring out what each variable represent in the future or in a long program.
age = 50;
declares a variable called age and signs he integer value 50 to this variable.
The following shows some more examples of variables being created when a value is assigned to a variable:
sum = x = y = 0; // declares three variables and each is set to 0.
Alternatively, you may declare and assign the values using the var command:
var sum, x, y; // declares multiple variable with the var command.
sum = x = y = 0; // sets each variable to 0
So after reviewing the examples above you might be wondering what approach should you take to create variables? Well, as a matter of good programming practice, you should explicitly declare variables with the var command before using. Explicitly declaring a variable helps the browser efficiently and accurately process and manage the variables.