Postings list

The postings list is a data structure commonly used in information retrieval (IR) systems to store indexing information about a corpus. It is central to the design and efficiency of search engines and database management systems that need to retrieve information rapidly.

At the bare minimum, a postings list is associated with a term from a document and records the places where that term appears. Each term found in documents within a corpus is mapped to a corresponding postings list containing information such as the documents the term appears in and often the positions within those documents.