What is a cache?

The article explores the concept of caching, detailing its significance in enhancing application performance, resilience, and resource efficiency. It explains caching as a method of storing previously accessed data for easier retrieval and examines various types of caching relevant to frontend developers, such as JavaScript caching, HTTP caching, and service worker caching. The text emphasizes the challenges of cache invalidation and the need to balance data freshness with caching benefits. It also highlights backend caching and the importance of strategically removing unused or outdated cache entries to maintain efficiency. Throughout, the article underscores the complexity of caching and provides insights into its implementation and best practices in modern web development.