Simple 2 Dimensional Array

 var grades = [[89, 77, 78],[76, 82, 81],[91, 94, 89]];
 print(grades[2][2]); 

Method 1

var numeric = [
    ['input1','input2'],
    ['input3','input4']
];
numeric[0][0] == 'input1';
numeric[0][1] == 'input2';
numeric[1][0] == 'input3';
numeric[1][1] == 'input4';

Method 2

var obj = {
    'row1' : {
        'key1' : 'input1',
        'key2' : 'inpu2'
    },
    'row2' : {
        'key3' : 'input3',
        'key4' : 'input4'
    }
};
obj.row1.key1 == 'input1';
obj.row1.key2 == 'input2';
obj.row2.key1 == 'input3';
obj.row2.key2 == 'input4';

Method 3

var mixed = {
    'row1' : ['input1', 'inpu2'],
    'row2' : ['input3', 'input4']
};
obj.row1[0] == 'input1';
obj.row1[1] == 'input2';
obj.row2[0] == 'input3';
obj.row2[1] == 'input4';

Creating a Multidimensional Array on Fly

var row= 20;
var column= 10;
var f = new Array();

for (i=0;i<row;i++) {
 f[i]=new Array();
 for (j=0;j<column;j++) {
  f[i][j]=0;
 }
}

Method to create a Javascript Multidimensional Array

Array.matrix = function(numrows, numcols, initial) {
var arr = [];
for (var i = 0; i < numrows; ++i) {
var columns = [];
for (var j = 0; j < numcols; ++j) {
columns[j] = initial;
}
arr[i] = columns;
}
return arr;
}

Sample Test Values

var nums = Array.matrix(5,5,0);
print(nums[1][1]); // displays 0
var names = Array.matrix(3,3,"");
names[1][2] = "Joe";
print(names[1][2]); // display "Joe"