Update stack readme.md (#4678)

Author: AnujRathour

src/main/java/com/thealgorithms/datastructures/stacks/README.md

@@ -1,10 +1,14 @@
 # STACK
 
-Stack is an ADT (abstract data type) that acts like a list of objects but there is a difference.
+- Stack is an ADT (abstract data type) that is a collection of elements where items are added and removed from the end, known as the "top" of the stack.
 
-Stack works on the principle of _LIFO_ (Last In First Out), it means that the last item added to the stack will be the first item to be removed.
+- Stack works on the principle of _LIFO_ (Last In First Out), it means that the last item added to the stack will be the first item to be removed.
 
-Stack is based on two methods (functions)-
+## Declaration
+ `Stack<Obj> stack=new Stack<Obj>();`
+
+# Functionalities
+Stack is based on two functions (methods)-
 
 ## push(element)
 
@@ -29,3 +33,13 @@ It removes the last element (i.e. top of stack) from stack.
 For example: If we have `1, 3, 5 , 9` in stack, and we call pop(),
 
 the function will return `9` and the stack will change to `1, 3, 5`.
+
+# Real Life Applications 
+  - `Undo mechanisms:`
+     Many software applications use stacks to implement an "undo" feature.
+
+  - `Browser history:`
+    The "back" button in a web browser is implemented using a stack, allowing users to navigate through previously visited pages.
+
+  - `Function calls and recursion:` 
+    The computer's call stack keeps track of function calls, allowing programs to remember where to return after a function finishes execution.