What Is A Parameter?

Definition

When you take a look at mathematical formulas most of them usually have alphabets say x or y in them, and the intention is that anyone using these formulas will replace the x and ys with actual values. In the programming world functions can be viewed as these formulas and parameters will be the x and ys.

Use Cases and Examples

Here is an example of a function in Javascript that adds two parameters together:

Copy
01: // declaring the function
02: function adder(a, b) {
03:     return a+b;
04: }
05: 
06: // using the function
07: adder(1,2);

What you have above is a function called adder that takes two parameters and returns the sum of a and b. The last bit of the code shows how you will use this function. You will refer to the values you pass in to replace the parameters as arguments.

Summary

Parameters are key to how we end up getting different behaviors out of the same piece of code.

Here is another article you might like 😊 "What Is A Parser?"