In this lesson, we will explore the concept and practical use of Maps in TypeScript. Maps are a powerful and efficient data structure for storing key-value pairs. We'll use a Map to count the frequency of elements in a collection, understand its mechanics, and analyze its time and space efficiency. Through step-by-step demonstrations and detailed code examples, we'll uncover the practical applications of Maps in various contexts.

Imagine a paint store where we need to count the cans of paint in different colors. Manually counting each one becomes inefficient as the collection grows. A more efficient method employs a Map. Consider this list of colors:

Manually, red appears twice, blue three times, and green once. Using a Map can streamline this process.

Maps allow us to store and retrieve data using keys. In our example, the unique colors in our list are the keys and their counts are the values. Let's use TypeScript's Map to count elements in our colors list.

First, we'll initialize our Map to store the counts: