OnMouseOver
     --content change when we placed the mouse on the text
 OnMouseOut
     --content change when we placed out the mouse from the text
Objects
  --objects are just data with properties and methods
  --properties are values
  --methods are actions that objects does something
  --properties are the all variables
Create Own Objects
 --Special data types has its own properties and methods
 --We can create objects in many ways one of the easiest way is constructive function
 --function person(name, age)
{ this.name = name; this. age = age; }
 is a blueprint  of an object person
--var hasan = new person("Mainul Hasan", 24);
 --var mehedi = new person("Mehedi Hasan", 22); here, hasan and mehedi is the new instance of the person
--So now we can conclude that if we have a blueprint of an object then we create any number of instance of that object