Redis is an in-memory database that can store key/value pairs. It best suits the use case of storing heavy read-intensive data. For example, news agencies such as the BBC and The Guardian show the latest news articles on their dashboard. Their traffic is high and, if documents are to be fetched from the database, they have to maintain a huge cluster of databases at all times.
Since the given set of news articles does not change (for hours), an agency can maintain a cache of articles. When the first customer visits the page, a copy is pulled from the DB, placed in the Redis cache, and then sent to the browser. Then, for another customer, the news agency server reads content from Redis instead of hitting the DB. Since Redis runs in the primary memory, latency is minimal. As a result, the customer sees faster page loads. The benchmarks on the web...