Algolia's search indexing service transforms back-office data and file types into searchable data, enabling fast and relevant search on any device globally. It interfaces with every source of truth to provide a reliable and secure searchable data layer between the back-office data source and any front-end that serves data to users. Algolia's indexing foundation is crucial for serving all front-end search needs, as it decouples the back from the front end, creating a middle layer of searchable data. The company offers different levels of real-time indexing depending on the use case, with some scenarios requiring instantaneous updates and others needing regular updates every 30 minutes or overnight.