Client Type identifies an application where a search query is sent from. System client types are available out-of-the box, ...

Client Type identifies an application where a search query is sent from. System client types are available out-of-the box, and cannot be deleted. You can add a new custom client type by clicking on New Client Type.

Applications are prioritized by tiers. Top tier has the highest priority. When resource limit is reached, query throttling becomes ON, and search system will process the queries from top tier to bottom tier.