var myArray = Array();
myArray['A'] = "Athens";
myArray['B'] = "Berlin";

var myObject = {'A': 'Athens', 'B':'Berlin'};

var myArray = Array();
myArray['A'] = "Athens";
myArray['B'] = "Berlin";

alert(myArray.length);

concat
every
filer
forEach
join
indexOf
lastIndexOf
map
pop
push
reverse
shift
slice
some
sort
splice
toSource
toString
unshift
valueOf

javascript:alert([].length+'n'+{}.length)

javascript:
  ra=[  "one",   "two",   "three"]; ra.a=4;
  ob={0:"one", 1:"two", 2:"three"}; ob.a=4;
  alert(
    ra            +"nn"+
    ob            +"nn"+
    ra.toSource() +"nn"+
    ra.a          +"t .toSource() forgot me! nn"+
    ra.length     +"t and my length! nn"+
    ob.toSource());
  ps=""; for(i in ra)ps+=i+" "; alert(ps);  /* NB .length is missing! */
  ps=""; for(i in ob)ps+=i+" "; alert(ps);

javascript:
  ra=[  "one",   "two",   "three"]; ra.a=4;
  ob={0:"one", 1:"two", 2:"three"}; ob.a=4;
  alert(
    ra            +"nn"+
    ob            +"nn"+
    ra.toSource() +"nn"+
    ra.a          +"t .toSource() forgot me! nn"+
    ra.length     +"t and my length! nn"+
    ob.toSource());
  ps=""; for(i in ra)ps+=i+" "; alert(ps);  /* NB .length is missing! */
  ps=""; for(i in ob)ps+=i+" "; alert(ps);

0 1 2 a

javascript:
    alert([Array, Boolean, Date, Function,
              Number, Object, RegExp, String] . join('nn') );

function Array() {
    [native code]
}

function Boolean() {
    [native code]
}

function Date() {
    [native code]
}

function Function() {
    [native code]
}

function Number() {
    [native code]
}

function Object() {
    [native code]
}

function RegExp() {
    [native code]
}

function String() {
    [native code]
}

javascript:alert([Math, JSON, true.toSource()].join("nn"));

[object Math]

[object JSON]

(new Boolean(true))

var myArray = Array();

var myObject = {'A': 'Athens', 'B':'Berlin'};

alert(myArray.constructor)
alert(myObject.constructor)

var Func = new Function("<params>", "<code>");

var a = [];
a['name'] = 'John';
JSON.stringify(a); // will output '[]'

var b = {};
b['name'] = 'John';
JSON.stringify(b); // will output '{"name":"John"}'