when to use array var and when to use json ? code example

Example 1: json example array

{
	"name":"John",
	"age":30,
	"cars":[ "Ford", "BMW", "Fiat" ]
}

// Another exemple
{
    "people": [
        {
            "website": "stackabuse.com",
            "from": "Nebraska",
            "name": "Scott"
        },
        {
            "website": "google.com",
            "from": "US",
            "name": "Zuck"
        }
    ]
}

Example 2: hwo to access arary in json

console.log(dataJS);
console.log(dataJS[0].eee1);
console.log(dataJS[0].comments[0]);