text: Q:
  
  Object class in android
  
  What is the use of Object class in android. The documentation of android doesn't clearly clears what it means.
  eg ArrayList we use it store value of any type in particular key.
  But I am unable to find out whay is the analogy behind it.
  My last question is why to use that object class and in which circumstances we can use it
  
  A:
  
  The Object class, as others pointed out is like a 'Mother Class', which all other classes directly or indirectly derive from. That said, it's oftenly used as a 'Generic' class which you can use to return or pass arguments of ANY type. e.g. : You are creating a generic callback that can receive some types, you could define it as: myCallback(Object result){}, so, when passing this callback, you can cast it to any type you'd like, eg. Integer res = (Integer) result; or String res = (String) result; and so on.
  Object also has the toString method, that returns some information about your object eg:
  You have a Person class with String name and String lastName, you could override toString to do so toString(){ return this.name + " " + this.lastName; }.
  Another use of the Object class is when using the synchronized field (multithreading). eg:
  Object lock = new Object(); 
  public void anyConcurrentFunction(){
     synchronized(lock){
     do something here...
    }
  }
  
  And some other general stuff.
  Hope I could help !
  
  