How does JSONB differ from JSON in PostgreSQL?

PostgreSQL supports two JSON storage types. JSON stores JSON as text, preserving the original format including whitespace and duplicate keys — it validates JSON syntax but doesn't parse deeply. JSONB stores JSON in a decomposed binary format — it parses and validates fully, removes whitespace, removes duplicate keys (last value wins), and reorders keys. Key advantages of JSONB: supports indexing (GIN indexes), has more operators, and is much faster for querying/filtering. Query operators: -> (get JSON object), ->> (get as text), #> (path access), @> (contains), <@ (contained by), ? (key exists). Always prefer JSONB over JSON unless you specifically need to preserve insertion order or duplicate keys.