Welcome back! This tutorial focuses on JavaScript Maps — powerful data structures ideal for storing key-value pairs. With two illustrative problems, you'll sharpen your ability to create and operate Maps, walking away with crucial skills to solve real-world challenges.

Imagine we have a blog. We want to analyze the posts to see which topics are most discussed. A practical solution involves writing a function to count the frequency of each word in a blog post while ignoring case and punctuation.

This function is essential in text analysis tools used in search engine optimization. It can highlight popular topics and even suggest post tags, increasing visibility in search results.

Straight away, we might think to tally word occurrences — an extra tedious process manually! This would mean extra loops, slow performance, and our time is too valuable to be inefficient.

Instead, Maps are handy, allowing us to map each unique word to its frequency count effortlessly. With this in mind, we can track how often each word appears with far less code and do it faster!

Let's start by creating a function and cleaning up our input: remove punctuation and convert it to lowercase for consistency.

We split the cleaned text into various words, ready for counting.

We use the Map to keep track of the count for each word, incrementing it for each occurrence.