Instance Variable :
Declaration: A instance variable is declared inside the class but outside the methods ,blocks or constructors.
for example
class Math{
int a=10; // here a is a instance variable.
void add(){
int c=30,d ;
d=a+ b+ c;
System.out.println(d);
}}
Scope: Instance Variable can be used inside all methods ,blocks and constructors within a class( not inside the static method directly).
When variable gets memory allocated : Instance Variable gets memory allocated when the object is created, when objects get destroyed variable releases memory.
Stored memory : Instance variables are stored in heap memory(part of memory allocated to JVM).
Default value : Instance Variables have default values like Integer :0 , Boolean :false , object : null.
Access specifier : Access specifiers i.e, public protected, private can be used with Instance Variable.
How to access : Instance Variables can be called directly or by using object name.