
Apache Solr is an open-source enterprise search server.

Apache Solr is an open-source enterprise search server.
Guru is a knowledge platform designed to serve as what the vendor describes as an AI source of truth for enterprises. It connects information from tools like Slack, Teams, Google Workspace, Salesforce, and other systems into one governed, permission-aware knowledge layer. Guru delivers cited AI answers, chat, and research directly within existing workflows, to enable employees and AI assistants to access verified knowledge securely and efficiently. The platform combines enterprise search, AI…

Apache Solr is an open-source enterprise search server.
Amazon CloudSearch is enterprise search as a service, from Amazon Web Services.
IBM offers Watson Discovery, a natural language processing (NLP) application with options to measure sentiment, detect entities, semantic roles, and other concepts.

Azure AI Search (formerly Azure Cognitive Search) is enterprise search as a service, from Microsoft.
Guru is a knowledge platform designed to serve as what the vendor describes as an AI source of truth for enterprises. It connects information from tools like Slack, Teams, Google Workspace, Salesforce, and other systems into one governed, permission-aware knowledge layer. Guru delivers cited AI answers, chat, and research directly within existing workflows, to enable employees and AI assistants to access verified knowledge securely and efficiently. The platform combines enterprise search, AI…

Apache Solr is an open-source enterprise search server.
Amazon CloudSearch is enterprise search as a service, from Amazon Web Services.
IBM offers Watson Discovery, a natural language processing (NLP) application with options to measure sentiment, detect entities, semantic roles, and other concepts.
The Google Search Appliance provided document indexing. The product was discontinued in favor of Google's cloud-based options.

Azure AI Search (formerly Azure Cognitive Search) is enterprise search as a service, from Microsoft.