What is caching used for?

Caching is used for:

• Speeding up data access: Storing frequently used data in a fast storage (cache) reduces the time to retrieve it from slow sources (e.g., databases, external services).
• Reducing load: Fewer requests to primary data sources decrease their load, improving overall system performance.
• Reducing latency: Decreasing system response time through quick access to cached data.
• Ensuring resilience: In case the primary data source is unavailable, the cache can serve outdated but accessible data.

Examples of usage:

• Caching database query results.
• Caching data from external APIs.
• Caching rendered web pages or their fragments.
• Caching static resources (CSS, JS, images) in the browser.

Implementing caching involves choosing a strategy (e.g., LRU - Least Recently Used, LFU - Least Frequently Used), defining cache size, and cache invalidation (refresh) policies.