…I consider it a great data type
object's keys are unordered, usually ordered by name or by how properties were added.
array always preserves order of elements
Not for humans, so for better human writing emerged more forgiving formats, like JSON5 (ES5), HJSON and more. I wrote .NET implementation
There's a nice summary of all competing formats.
ER diagram editor, multipurpose
Canvas or SVG
Arrow heads