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array of numbers
subject			fact

array of numbers	is a subtopic of Arrays
	is initialized automatically so that every element has the value 0
	is a kind of array
array	can be composed of primitive types or instances of classes
	has a fixed size
	has a mechanism for preventing access outside the bounds of the array
	has a type which is the type of every data item in the array
	has example //the following sums all the elements of an integer array: for(int i = 0; i < anIntArray.length; i++) { sum += anIntArray[i]; }
	has example of creation //Create an array called numbers containing 4 integers int numbers; numbers = new int [4]; //Or create the array combining the two statements into one int numbers [] = new int [4]; //Or create the array and initialize it too int numbers [] = {1, 2, 3, 4};
	has length stored in the instance variable length
	is more efficient than specialized collection classes
	is object-like but is not a true instance of a class
	is zero-based which means the first element is element 0
	is created using the new operator
	is declared using an array declaration
	is initialized to default values if it is created using new numerical arrays contain all 0's Boolean arrays set every element to false character arrays contain all '\0' arrays of objects contain all null
	is not an instance of a class which you can subclass or for which you can write your own code
	should be avoided if you do not know beforehand the number of items it will contain
	should not be used to manipulate collections of objects
object	when an object is created the object's variables are set to default values the constructor of the object's superclass is invoked the object's initialization block is invoked the object's constructor is invoked
	object is not cloneable unless you implement the Cloneable interface and you override the clone method for the object's class
	when an object is created then the runtime system creates space for each of the object's instance variables
	when an object is not needed any longer the object's space is garbage collected
	can access all instance variables of all objects of its class
	can be converted into a string using the toString method
	can be referred to without reference to the instance variables contained in it
	can be referred to by several different variables at the same time
	can communicate with every object to which it has access through its public interface
	can convert itself to a string representation using the toString method
	can model a real-world object or an abstract concept
	can notify other objects that a condition variable has changed
	can receive messages from objects in the same process objects in different processes objects on the same machine objects on different machines
	can represent any entity to which you can associate properties and behaviour
	can return its class using the getClass method
	can send messages to objects in the same process objects in different processes objects on the same machine objects on different machines
	can wait on 0 or more condition variables
	communicates with other objects by sending and receiving messages
	has part public interface
	hides methods from other objects using the 'private' keyword
	inherits instance methods and instance variables from the class to which it belongs all that class's superclasses
	is created by declaring and initializing it such that it is created whenever execution enters a particular block, or, in the case of an instance variable, when an instance is created, for example: String aString = "some text"; or by declaring it and initializing it later using the new operator, for example: String aString; aString = new String("some text");
	shares every instance method of its class with the other instances of its class
	shares its implementation with other instances of its class
	shares one copy of each class variable of its class with the other instances of its class
	to create you use the new operator

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