https://www.postgresql.org/docs/current/static/hstore.html
This module implements the hstore data type for storing sets of
key/value pairs within a single PostgreSQL value
t=# select ('height=>190, color=>black')::hstore;
hstore
-----------------------------------
"color"=>"black", "height"=>"190"
(1 row)
https://www.postgresql.org/docs/current/static/datatype-json.html
JSON data types are for storing JSON (JavaScript Object Notation)
data, as specified in RFC 7159. Such data can also be stored as text,
but the JSON data types have the advantage of enforcing that each
stored value is valid according to the JSON rules.
t=# select '{"height":190, "color":"black"}'::json;
json
---------------------------------
{"height":190, "color":"black"}
(1 row)