JavaScript maps vs. sets: Choosing your data structure

JavaScript's data structures have evolved significantly, especially with the ECMAScript 2015 specification, which introduced new standard inbuilt types like Symbol, Promise, and Proxy, as well as keyed collections such as Map and Set. These structures are essential for efficient data manipulation, offering optimized solutions for common programming problems. For instance, Maps store key/value pairs with unique keys, allowing for efficient data retrieval and updates, while Sets maintain unique values, simplifying tasks like duplicate removal. The SameValueZero algorithm ensures accurate key comparisons in Maps, even with special values like NaN, while Sets utilize it to maintain distinct values efficiently. The document explores various methods to iterate over and manipulate these collections, emphasizing the importance of selecting the appropriate data structure for specific tasks, such as using Map for two-dimensional storage needs or Set for storing unique items. Practical applications include solving algorithmic problems, implementing caches with eviction strategies, and representing graphs using adjacency lists. These structures are vital for modern JavaScript development, providing powerful tools to handle complex data operations efficiently.