If you have a website the performance of which isn’t that fast, think about elasticache. With elasticache the cached heavy content on webpages tends to load faster enhancing the site’s performance. How is it done? Through the in-memory data store.
Elasticache is used to provide fast and cheap access to data copies. A database with joins across numerous tables or intensive calculation queries will be slow and expensive while querying than, for example, finding keys in a key-value pair cache. Also, it is possible to retrieve the data a number of times without the query being re-executed.
Getting data from a database rather than from a cache is slower and requires more costs. Data requiring slow and expensive query has to be cached. The quick and simple query has to be cached as well, but it depends.
Before caching items it is necessary to get to know what is data and what are its access patterns. For example, the data should be static and frequently accessed to be cached. This might be a personal profile on social media.
Any data should be stale data to cache it. If the app you have has stale data then you can use elasticache.
To find out more, follow the link to the Caching Strategies.