As Js can handle lot of types in the same bunch ( like complex arrays do : type / function / object / strings ),
json comes here, and is so compliant with Js and DOM
serializable means that a json pattern could be build :
- with multi-dimensionnal array grounding a hierarchy for Datas constraints and organisation.
- the pairs : key:value
- complex types in : function / object / single var all types
In the other languages, to stock all data types : It's "variant" / "object" types.
but Js and Json in a web browser are loaded, before all as "a big string" ( with its File from server ),
then in the DOM as part of it.
then the Js engine parse and execute all in the dom.
if you're interested by complex arrays and lots of types in,
read the jquery code API, you'll see it's only JS.
lot of API for web browser are JS at high skill. It's all objects and complex arrays.
JSON appears with the NOSQL database after year 2000' ( born before ~1997 ),
because its purpose is a container for all datas in a row of a db or file.
It's 'blob'