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MongoDB uses BSON, a binary serialization format, to store documents and to exchange data. BSON is a rich format and has data types that aren't included in the JSON standard. Extended JSON (EJSON) adds support for the additional types. EJSON is a JSON compatible way to represent BSON values.
Convert Extended JSON objects to BSON objects. This method is useful to import JSON data from external applications.
Convert BSON objects to strings. This method is useful to transform
Convert strings to JSON. This method is useful to transform inputs.
For additional EJSON capabilities, see the npm EJSON documentation.