Elasticsearch mapping is used to define the document structure with available fields and their datatypes. In Elasticsearch mapping, we have two types of fields, user-defined fields or properties and meta fields. User-defined fields can be any field that we use to provide for mapping or indexing while meta fields are those fields that help us to identify associated document metadata, for example, _index, _id, and _source.
Mapping
Datatypes
Each field in an Elasticsearch document can have a datatype, and the datatype can be categorized into three categories, which are as follows.