[Znafon]

They have a useful list of feature that you can look at: https://www.algolia.com/products/search/

It's basically a service that you can use so users can search objects in your database, a bit like Google but just for your website or application.

[rvnx]

Isn't it exactly what a managed Elasticsearch does ?

[BrigadierG]

Yes but vastly faster, and requires less setup.