The document discusses using ElasticSearch to enable fast and scalable search of reviews. It describes how ElasticSearch allows for tokenization, stemming, stop words removal and faceting to improve search performance compared to a basic SQL search. An example query and response show how ElasticSearch returns search results and highlights matching text. The document also briefly outlines how data could be indexed in ElasticSearch through a queueing system and how shards and replicas can provide replication and scalability. It closes by noting some potential performance issues to be aware of with ElasticSearch.