findArrayIntersection()

Step 1: Understand the Problem Statement

Before we start, we need to understand the problem statement. We are asked to create a function named findArrayIntersection. This function will take two arrays as input arguments and return the intersection, or the common elements, of these two arrays.

Step 2: Define the Function Signature

Now, let's begin by defining the function signature and writing out the pseudocode for findArrayIntersection in Javascript.

function findArrayIntersection(array1, array2) {
    // Pseudocode: 
    // Create an empty array to store the intersected elements
    // Iterate over the first array
            // Check for each element if it exists in the second array.
            // If so, add this element to the intersected array
}

Step 3: Declare an Intersected Array

Next, declare an empty array where you would store the intersected elements.

function findArrayIntersection(array1, array2) {
    let intersected = [];
    //...
}

Step 4: Implement Loop to Traverse the Array

At this step, add a loop to traverse through the elements in the first array. Inside the loop, verify whether the current element exists in the second array. If it does, this means it's an intersection element and should be added to the "intersected" array.

function findArrayIntersection(array1, array2) {
    let intersected = [];
    for(let i=0; i<array1.length; i++){
        if(array2.includes(array1[i])){
            intersected.push(array1[i]);
        }
    }
    //...
}

Step 5: Return the Intersected Array

Finally, return the "intersected" array which contains the common elements from both input arrays.

function findArrayIntersection(array1, array2) {
    let intersected = [];
    for(let i=0; i<array1.length; i++){
        if(array2.includes(array1[i])){
            intersected.push(array1[i]);
        }
    }
    return intersected;
}

Conclusion

Here we have it, an easy-to-understand implementation of a function for finding the intersection of two arrays using JavaScript. This function efficiently loops through each item in the first array, and checks whether this item also exists in the second array by leveraging the built-in includes() method in JavaScript. When a common item is found, it is stored in the intersect 'intersected' array, which is returned as the final output once the loop ends.