Enterprise search

Enterprise search is search across an organisation's internal systems, returning results from documents, tickets, messages, and applications while respecting each user's existing permissions.

The defining constraint is permissions. A public web index can show everyone the same results; an internal index cannot, because two people searching the same phrase must see different results depending on what they are allowed to open.

Retrieval quality is the second constraint. Internal content is full of drafts, superseded versions, and half-finished pages, so a system that ranks purely on keyword match will confidently surface a document that was overruled two years ago.

Search answers where something is. It does not answer why a decision was made, which is the question most internal searches are really asking.