public static void inOrder(Node root) {
    // Base Case: If the node is null, return (end recursion)
    if (root == null) {
        return;
    }

    // Recursive Step: Traverse the left subtree
    inOrder(root.left);

    // Process the current node (print its value)
    System.out.print(root.data + " ");

    // Recursive Step: Traverse the right subtree
    inOrder(root.right);
}