This is pretty cut and dry, just set up a nested loop:

var count = 1;
var twoDimensionalArray =[];

for (var i=0;i<2;i++)
{
  var data = [];
  for (var j=0;j<5;j++)
  {
    data.push("Test" + count);
    count++;
  }

  twoDimensionalArray.push(data);

}

Practically? Yes. You can create an array of arrays which functions as an 2D array as every item is an array itself:

let items = [
  [1, 2],
  [3, 4],
  [5, 6]
];
console.log(items[0][0]); // 1
console.log(items[0][1]); // 2
console.log(items[1][0]); // 3
console.log(items[1][1]); // 4
console.log(items);

But technically this is just an array of arrays and not a “true” 2D array, as I. J. Kennedy pointed out.

It should be noted that you could keep nesting arrays into one another and so create “multidimensional” arrays.

If you mean an object (as in your example), and want to use variables as keys, you'll have to split the declaration in multiple lines, and use bracket notation:

var tblObj = { main1: {}, main2: {} };
tblObj.main1[var2] = var3;
tblObj.main1[var3] = var4;
tblObj.main2[var5] = var6;

(Assuming all those variables are already defined.)

if (!globalArray[index]) 
    globalArray[index] = []; // init the array.

globalArray[index].push(name);

You have a typo with the dot:

$.("#uname").val(); 

Change to:

$("#uname").val();

What are you trying to do with this code?

Update: (The question was totally edited.)

Your code:

var globalArray[0] = new Array(); 

globalArray[0] is invalid variable name, you need first to declare the array:

var globalArray = []; // Array literal.
globalArray[0] =  [] // The element at position 0 is new an array. 

You do not Dim the Array to an actual size,

You can just set an variable on any index to whatever you want

if you want two Dimensions you just could define an array

var arr = []

set an element to another array

arr[0] = []

and put an value inside an element in the "2nd dimension"

arr[0][10] = 10

You only have the elements in the "first dimension" to be an array

You could also do things like placing arrays into arrays

like

var arr = []
var arr1 = [1,2,3]
arr[0] = arr1
console.log(arr[0][2]) //3

And if you have an array and want to push elements in an inner array just do a check if the element is defined, like

var arr = []
for ( var i = 0; i < 5 ; i++) {
    if(!arr[i])
        arr[i] = []
    for ( var j = 0; j < 3 ; j++)
        arr[i][j] = i + " - " + j // Or like this,
        //arr[i].push(i + " " + j) // 
}
console.log( arr[2][3]) // 2 - 3

Given the Code you posted

function newTest() {
    var myArray = [[],[]];
  //  myArray[] = new Array(14);

    var recCount = 15
    var n =0;

    var i = 0;
    var s = 0;

    for (i = 0; i < recCount; i++) {
        if(!myArray[i])
             myArray[i] = []
        for (s = 0; s < 15; s++) {
            console.log(i)

          //  myArray[i] = new Array(14);

            myArray[i][s] = s;
            n++;

          //  alert("i=" + i + " s=" + s + " Val: " + (myArray[i][s]));

        }
        // var u = 4;
        s = 0;

        alert(myArray[0][3]);
        alert(myArray[0][4]);

        alert("i=" + i + " s=" + s + " Val: " + (myArray[i][s]));              

    }
}
newTest()

This works for me

​

Pure JavaScript:

var newData = [];
var sampledata = [10,20,30,40];
for (var i = 0; i < sampledata.length; i++) {
    newData.push([i, sampledata[i]]);
}

Using higher-order functions:

var newData = sampledata.map(function(el, i) {
    return [i, el];
})