diff --git a/Arrays/Anagram_Check_manual_Sol.py b/Arrays/AnagramCheckManualSol.py
similarity index 100%
rename from Arrays/Anagram_Check_manual_Sol.py
rename to Arrays/AnagramCheckManualSol.py
diff --git a/Arrays/Anagram_Check_Sorted_Sol.py b/Arrays/AnagramCheckSortedSol.py
similarity index 100%
rename from Arrays/Anagram_Check_Sorted_Sol.py
rename to Arrays/AnagramCheckSortedSol.py
diff --git a/Arrays/ArrayFindTheMissingElement_brute_force_sol.py b/Arrays/ArrayFindTheMissingElementBruteForceSol.py
similarity index 100%
rename from Arrays/ArrayFindTheMissingElement_brute_force_sol.py
rename to Arrays/ArrayFindTheMissingElementBruteForceSol.py
diff --git a/Arrays/ArrayFindTheMissingElement_hash_table_sol.py b/Arrays/ArrayFindTheMissingElementHashTableSol.py
similarity index 100%
rename from Arrays/ArrayFindTheMissingElement_hash_table_sol.py
rename to Arrays/ArrayFindTheMissingElementHashTableSol.py
diff --git a/Arrays/ArrayFindTheMissingElement_takingSumandSubtract_sol.py b/Arrays/ArrayFindTheMissingElementSumSol.py
similarity index 100%
rename from Arrays/ArrayFindTheMissingElement_takingSumandSubtract_sol.py
rename to Arrays/ArrayFindTheMissingElementSumSol.py
diff --git a/Arrays/ArrayFindTheMissingElement_XOR_sol.py b/Arrays/ArrayFindTheMissingElementXORSol.py
similarity index 100%
rename from Arrays/ArrayFindTheMissingElement_XOR_sol.py
rename to Arrays/ArrayFindTheMissingElementXORSol.py
diff --git a/Arrays/README.md b/Arrays/README.md
index 707a82e..8cbf800 100644
--- a/Arrays/README.md
+++ b/Arrays/README.md
@@ -4,10 +4,10 @@ This directory contains Python implementations of common array-based algorithms
 
 ## Contents
 
-- [Anagram Check (Sorted Solution)](Anagram_Check_Sorted_Sol.py): Checks if two strings are anagrams by comparing their sorted versions.
-- [Anagram Check (Manual Solution)](Anagram_Check_manual_Sol.py): Checks if two strings are anagrams using a hash table (dictionary) to count character frequencies.
-- [Array Find Missing Element (XOR Solution)](ArrayFindTheMissingElement_XOR_sol.py): Efficiently finds a missing element in a shuffled array using bitwise XOR.
-- [Array Find Missing Element (Brute Force Solution)](ArrayFindTheMissingElement_brute_force_sol.py): Finds a missing element by sorting both arrays and comparing them.
-- [Array Find Missing Element (Hash Table Solution)](ArrayFindTheMissingElement_hash_table_sol.py): Finds a missing element using a hash table (dictionary) to track element counts.
-- [Array Find Missing Element (Sum/Subtract Solution)](ArrayFindTheMissingElement_takingSumandSubtract_sol.py): Finds a missing element by calculating the difference between the sums of the two arrays.
+- [Anagram Check (Sorted Solution)](AnagramCheckSortedSol.py): Checks if two strings are anagrams by comparing their sorted versions. Complexity: $O(n \log n)$.
+- [Anagram Check (Manual Solution)](AnagramCheckManualSol.py): Checks if two strings are anagrams using a hash table (dictionary) to count character frequencies. Complexity: $O(n)$.
+- [Array Find Missing Element (XOR Solution)](ArrayFindTheMissingElementXORSol.py): Efficiently finds a missing element in a shuffled array using bitwise XOR. Complexity: $O(n)$.
+- [Array Find Missing Element (Brute Force Solution)](ArrayFindTheMissingElementBruteForceSol.py): Finds a missing element by sorting both arrays and comparing them. Complexity: $O(n \log n)$.
+- [Array Find Missing Element (Hash Table Solution)](ArrayFindTheMissingElementHashTableSol.py): Finds a missing element using a hash table (dictionary) to track element counts. Complexity: $O(n)$.
+- [Array Find Missing Element (Sum/Subtract Solution)](ArrayFindTheMissingElementSumSol.py): Finds a missing element by calculating the difference between the sums of the two arrays. Complexity: $O(n)$.
 - [Array Pair Sum Solution](ArrayPairSumSol.py): Finds all unique pairs in an array that sum up to a specific value $k$ using a set for $O(n)$ complexity.
diff --git a/deque/DequeImple.py b/Deque/DequeImple.py
similarity index 100%
rename from deque/DequeImple.py
rename to Deque/DequeImple.py
diff --git a/deque/README.md b/Deque/README.md
similarity index 75%
rename from deque/README.md
rename to Deque/README.md
index 046a17f..dd145b4 100644
--- a/deque/README.md
+++ b/Deque/README.md
@@ -5,3 +5,5 @@ This directory contains Python implementations of the Deque (Double-Ended Queue)
 ## Contents
 
 - [Deque Implementation](DequeImple.py): Basic implementation of a Deque using a Python list. Includes operations like `addFront`, `addRear`, `removeFront`, `removeRear`, `isEmpty`, and `size`.
+  - `addFront` and `removeFront`: $O(1)$
+  - `addRear` and `removeRear`: $O(n)$ (due to list shifting)
diff --git a/Error-debug/ErrorExceptions.py b/ErrorHandling/ErrorExceptions.py
similarity index 100%
rename from Error-debug/ErrorExceptions.py
rename to ErrorHandling/ErrorExceptions.py
diff --git a/Error-debug/README.md b/ErrorHandling/README.md
similarity index 100%
rename from Error-debug/README.md
rename to ErrorHandling/README.md
diff --git a/README.md b/README.md
index b8de7d5..d9a7ca4 100644
--- a/README.md
+++ b/README.md
@@ -35,23 +35,25 @@ See [CONTRIBUTING.md](CONTRIBUTING.md) for more details.
 
 ## 📖 Table of Contents
 
-- [Getting Started](#getting-started)
-- [Project Structure](#project-structure)
-- [Data Structures](#data-structures)
-  - [Arrays](#arrays)
-  - [Linked Lists](#linked-lists)
-  - [Stacks](#stacks)
-  - [Queues](#queues)
-  - [Deque](#deque)
-  - [Trees](#trees)
-- [Algorithms](#algorithms)
-  - [Sorting](#sorting)
-  - [Recursion & Dynamic Programming](#recursion--dynamic-programming)
-  - [Graph Algorithms](#graph-algorithms)
-- [Error Handling & Debugging](#error-handling--debugging)
-- [Usage](#usage)
-- [Quick Reference](#quick-reference)
-- [License](#license)
+- [About This Repository](#-about-this-repository)
+- [Contributing](#-contributing)
+- [Getting Started](#-getting-started)
+- [Project Structure](#-project-structure)
+- [Data Structures](#-data-structures)
+  - [Arrays](#arrays-)
+  - [Linked Lists](#linked-lists-)
+  - [Stacks](#stacks-)
+  - [Queues](#queues-)
+  - [Deque](#deque-)
+  - [Trees](#trees-)
+- [Algorithms](#-algorithms)
+  - [Sorting](#sorting-)
+  - [Recursion & Dynamic Programming](#recursion--dynamic-programming-)
+  - [Graph Algorithms](#graph-algorithms-)
+- [Error Handling & Debugging](#-error-handling--debugging)
+- [Usage](#-usage)
+- [Quick Reference](#-quick-reference)
+- [License](#-license)
 
 ---
 
@@ -67,7 +69,7 @@ Most scripts in this repository are standalone and can be executed directly:
 
 ```bash
 # Run any Python script
-python3 Arrays/Anagram_Check_Sorted_Sol.py
+python3 Arrays/AnagramCheckSortedSol.py
 
 # Or run from the repo root
 python3 Sorting/BubbleSortImple.py
@@ -80,7 +82,8 @@ python3 Sorting/BubbleSortImple.py
 ```
 .
 ├── Arrays/              # 🔤 Array-based problems and algorithms
-├── Error-debug/         # ⚠️ Error handling and debugging examples
+├── Deque/               # 🔄 Double-ended queue
+├── ErrorHandling/       # ⚠️ Error handling and debugging examples
 ├── GraphAlgorithms/     # 🗺️ Graph traversal (BFS, DFS) and pathfinding
 ├── LinkedLists/         # 🔗 Singly and Doubly Linked Lists
 ├── Queues/              # 📦 Queue implementations (FIFO)
@@ -88,7 +91,6 @@ python3 Sorting/BubbleSortImple.py
 ├── Sorting/             # 📊 Common sorting algorithms
 ├── Stacks/              # 📚 Stack implementations and applications
 ├── Trees/               # 🌳 Binary Trees, BSTs, Heaps, and Traversals
-├── deque/               # 🔄 Double-ended queue
 ├── CONTRIBUTING.md      # 🤝 Contribution guidelines
 ├── LICENSE              # 📄 MIT License
 └── README.md            # 📖 This file
@@ -100,40 +102,40 @@ python3 Sorting/BubbleSortImple.py
 
 ### Arrays 🔤
 Common array-based algorithms and manipulations.
-- [Anagram Check](Arrays/): [Sorted](Arrays/Anagram_Check_Sorted_Sol.py) & [Manual](Arrays/Anagram_Check_manual_Sol.py) solutions
-- [Array Pair Sum](Arrays/ArrayPairSumSol.py): Find pairs that sum to $k$
-- [Find Missing Element](Arrays/): [XOR](Arrays/ArrayFindTheMissingElement_XOR_sol.py), [Brute Force](Arrays/ArrayFindTheMissingElement_brute_force_sol.py), [Hash Table](Arrays/ArrayFindTheMissingElement_hash_table_sol.py), & [Sum](Arrays/ArrayFindTheMissingElement_takingSumandSubtract_sol.py) approaches
+- [Anagram Check](Arrays/): [Sorted](Arrays/AnagramCheckSortedSol.py) ($O(n \log n)$) & [Manual](Arrays/AnagramCheckManualSol.py) ($O(n)$) solutions
+- [Array Pair Sum](Arrays/ArrayPairSumSol.py): Find pairs that sum to $k$ ($O(n)$)
+- [Find Missing Element](Arrays/): [XOR](Arrays/ArrayFindTheMissingElementXORSol.py) ($O(n)$), [Brute Force](Arrays/ArrayFindTheMissingElementBruteForceSol.py) ($O(n \log n)$), [Hash Table](Arrays/ArrayFindTheMissingElementHashTableSol.py) ($O(n)$), & [Sum](Arrays/ArrayFindTheMissingElementSumSol.py) ($O(n)$) approaches
 
 ### Linked Lists 🔗
 Implementations and problems involving linked structures.
 - [Singly Linked List](LinkedLists/SingleLinkedListImple.py) & [Doubly Linked List](LinkedLists/DoublyLinkedListImple.py)
-- [Cycle Detection](LinkedLists/SinglyLinkedListCycleCheckImple.py): Detect cycles using two pointers (Floyd's algorithm)
-- [Reverse Linked List](LinkedLists/LinkedListReversal.py): In-place reversal
-- [Nth to Last Node](LinkedLists/LinkedListNthToLastNode.py): Find the $n$-th node from the end
+- [Cycle Detection](LinkedLists/SinglyLinkedListCycleCheckImple.py): Detect cycles using two pointers (Floyd's algorithm - $O(n)$)
+- [Reverse Linked List](LinkedLists/LinkedListReversal.py): In-place reversal ($O(n)$)
+- [Nth to Last Node](LinkedLists/LinkedListNthToLastNode.py): Find the $n$-th node from the end ($O(n)$)
 
 ### Stacks 📚
 LIFO (Last-In-First-Out) data structures.
-- [Stack Implementation](Stacks/StackImple.py): Basic operations (push, pop, peek)
-- [Balanced Parentheses](Stacks/BalanceParenthlessCheckImple.py): Check for balanced brackets using a stack
+- [Stack Implementation](Stacks/StackImple.py): Basic operations (push, pop, peek - $O(1)$)
+- [Balanced Parentheses](Stacks/BalanceParenthlessCheckImple.py): Check for balanced brackets using a stack ($O(n)$)
 
 ### Queues 📦
 FIFO (First-In-First-Out) data structures.
-- [Queue Implementation](Queues/QueueImple.py): Basic operations (enqueue, dequeue)
-- [Queue with Two Stacks](Queues/QueueWith2StacksImple.py): Implementing FIFO using LIFO structures
+- [Queue Implementation](Queues/QueueImple.py): Basic operations (enqueue - $O(n)$, dequeue - $O(1)$)
+- [Queue with Two Stacks](Queues/QueueWith2StacksImple.py): Implementing FIFO using LIFO structures (amortized $O(1)$)
 
 ### Deque 🔄
 Double-ended queue operations.
-- [Deque Implementation](deque/DequeImple.py): Operations at both ends
+- [Deque Implementation](Deque/DequeImple.py): Operations at both ends (`addFront`/`removeFront` - $O(1)$, `addRear`/`removeRear` - $O(n)$)
 
 ### Trees 🌳
 Hierarchical data structures.
-- [Binary Search Tree](Trees/BinarySearchTreesImple.py): Complete BST implementation
-- [BST Validation](Trees/): [Solution 1 (In-order)](Trees/BinarySearchTreeCheckImpleSol1.py) & [Solution 2 (Range check)](Trees/BinarySearchTreeCheckImpleSol2.py)
-- [Binary Search](Trees/): [Iterative](Trees/BinarySearchImple.py) & [Recursive](Trees/BinarySearchRecursiveImple.py)
+- [Binary Search Tree](Trees/BinarySearchTreesImple.py): Complete BST implementation ($O(\log n)$ average)
+- [BST Validation](Trees/): [Solution 1 (In-order)](Trees/BinarySearchTreeCheckImpleSol1.py) & [Solution 2 (Range check)](Trees/BinarySearchTreeCheckImpleSol2.py) ($O(n)$)
+- [Binary Search](Trees/): [Iterative](Trees/BinarySearchImple.py) & [Recursive](Trees/BinarySearchRecursiveImple.py) ($O(\log n)$)
 - [Binary Heap](Trees/BinaryHeapImple.py): Min-heap implementation
-- [Tree Traversals](Trees/TreeLevelOrderPrintImple.py): Level order (BFS) printing
-- [Trim BST](Trees/TrimBinarySearchTreeImple.py): Keep nodes within a range
-- [Tree Representations](Trees/): [Nodes & References](Trees/TreeRepresentationWithNodesReferences.py) & [List of Lists](Trees/buildTreeTest.py)
+- [Tree Traversals](Trees/TreeLevelOrderPrintImple.py): Level order (BFS) printing ($O(n)$)
+- [Trim BST](Trees/TrimBinarySearchTreeImple.py): Keep nodes within a range ($O(n)$)
+- [Tree Representations](Trees/): [Nodes & References](Trees/TreeRepresentationWithNodesReferences.py) & [List of Lists](Trees/BuildTreeTest.py)
 
 ---
 
@@ -144,31 +146,31 @@ Algorithms for arranging elements in order.
 - [Bubble Sort](Sorting/BubbleSortImple.py) - $O(n^2)$
 - [Selection Sort](Sorting/SelectionSortImple.py) - $O(n^2)$
 - [Insertion Sort](Sorting/InsertionSortImple.py) - $O(n^2)$
-- [Shell Sort](Sorting/ShellSortImple.py) - $O(n \log n)$
+- [Shell Sort](Sorting/ShellSortImple.py) - $O(n^2)$
 - [Merge Sort](Sorting/MergeSortImple.py) - $O(n \log n)$
 - [Quick Sort](Sorting/QuickSortImple.py) - $O(n \log n)$ average
 
 ### Recursion & Dynamic Programming 🔀
 Solving problems by breaking them into smaller sub-problems.
-- [Fibonacci Sequence](Recursion/): [Iterative](Recursion/FibonacciSeqIterative.py), [Recursive](Recursion/FibonacciSeqRecursion.py), & [Dynamic Programming](Recursion/FibonacciSeqDynamic.py)
-- [Coin Change Problem](Recursion/): [Recursive](Recursion/CoinChangeProblemRecursion.py) & [Dynamic Programming](Recursion/CoinChangeProblemDynamic.py)
-- [String Operations](Recursion/): [Reverse](Recursion/RecursionReverseStr.py) & [Permutations](Recursion/RecursionStrPermutation.py)
-- [Math Operations](Recursion/): [Cumulative Sum](Recursion/RecursionCumulativeSum.py) & [Sum of Digits](Recursion/RecursionSumOfDigits.py)
+- [Fibonacci Sequence](Recursion/): [Iterative](Recursion/FibonacciSeqIterative.py) ($O(n)$), [Recursive](Recursion/FibonacciSeqRecursion.py) ($O(2^n)$), & [Dynamic Programming](Recursion/FibonacciSeqDynamic.py) ($O(n)$)
+- [Coin Change Problem](Recursion/): [Recursive](Recursion/CoinChangeProblemRecursion.py) (Exponential) & [Dynamic Programming](Recursion/CoinChangeProblemDynamic.py) ($O(n \cdot m)$)
+- [String Operations](Recursion/): [Reverse](Recursion/RecursionReverseStr.py) ($O(n)$) & [Permutations](Recursion/RecursionStrPermutation.py) ($O(n!)$)
+- [Math Operations](Recursion/): [Cumulative Sum](Recursion/RecursionCumulativeSum.py) ($O(n)$) & [Sum of Digits](Recursion/RecursionSumOfDigits.py) ($O(\log_{10} n)$)
 - [Word Split](Recursion/RecursionWordSplit.py): Dynamic Programming solution
 
 ### Graph Algorithms 🗺️
 Algorithms for graph traversal and pathfinding.
 - [Adjacency List](GraphAlgorithms/AdjacencyListGraphImple.py): Graph ADT implementation
-- [Breadth First Search (BFS)](GraphAlgorithms/BFS.py): Word Ladder problem
-- [Depth First Search (DFS)](GraphAlgorithms/DFSGeneral.py): General DFS implementation
-- [Knight's Tour Problem](GraphAlgorithms/): [Graph Generation](GraphAlgorithms/TheKnightsTourProblem.py) & [DFS Solution](GraphAlgorithms/DFSImpleTheKnightsTourProblem.py)
+- [Breadth First Search (BFS)](GraphAlgorithms/BFS.py): Word Ladder problem ($O(V+E)$)
+- [Depth First Search (DFS)](GraphAlgorithms/DFSGeneral.py): General DFS implementation ($O(V+E)$)
+- [Knight's Tour Problem](GraphAlgorithms/): [Graph Generation](GraphAlgorithms/TheKnightsTourProblem.py) & [DFS Solution](GraphAlgorithms/DFSImpleTheKnightsTourProblem.py) ($O(k^N)$)
 - [Word Ladder Problem](GraphAlgorithms/WordLadderProblem.py): Building the word ladder graph
 
 ---
 
 ## ⚠️ Error Handling & Debugging
 
-- [Error and Exceptions](Error-debug/ErrorExceptions.py): Demonstrates `try`, `except`, `else`, and `finally` blocks for robust error handling.
+- [Error and Exceptions](ErrorHandling/ErrorExceptions.py): Demonstrates `try`, `except`, `else`, and `finally` blocks for robust error handling.
 
 ---
 
diff --git a/Trees/buildTreeTest.py b/Trees/BuildTreeTest.py
similarity index 100%
rename from Trees/buildTreeTest.py
rename to Trees/BuildTreeTest.py
diff --git a/Trees/README.md b/Trees/README.md
index 2047225..2ec20a6 100644
--- a/Trees/README.md
+++ b/Trees/README.md
@@ -5,19 +5,19 @@ This directory contains Python implementations of various tree-based data struct
 ## Contents
 
 ### Binary Search Trees (BST)
-- [Binary Search Tree Implementation](BinarySearchTreesImple.py): A comprehensive implementation of a BST with `TreeNode` and `BinarySearchTree` classes, including insertion, deletion, and search.
-- [Validate BST (Solution 1)](BinarySearchTreeCheckImpleSol1.py): Validates a BST by performing an in-order traversal and checking if the resulting values are sorted.
-- [Validate BST (Solution 2)](BinarySearchTreeCheckImpleSol2.py): Validates a BST by keeping track of the minimum and maximum allowable values for each node.
-- [Trim a BST](TrimBinarySearchTreeImple.py): Trims a BST so that all node values fall within a specified range $[min, max]$.
+- [Binary Search Tree Implementation](BinarySearchTreesImple.py): A comprehensive implementation of a BST with `TreeNode` and `BinarySearchTree` classes, including insertion, deletion, and search. Average complexity: $O(\log n)$.
+- [Validate BST (Solution 1)](BinarySearchTreeCheckImpleSol1.py): Validates a BST by performing an in-order traversal and checking if the resulting values are sorted. Complexity: $O(n)$.
+- [Validate BST (Solution 2)](BinarySearchTreeCheckImpleSol2.py): Validates a BST by keeping track of the minimum and maximum allowable values for each node. Complexity: $O(n)$.
+- [Trim a BST](TrimBinarySearchTreeImple.py): Trims a BST so that all node values fall within a specified range $[min, max]$. Complexity: $O(n)$.
 
 ### Search Algorithms
-- [Binary Search (Iterative)](BinarySearchImple.py): Iterative implementation of the binary search algorithm on a sorted list.
-- [Binary Search (Recursive)](BinarySearchRecursiveImple.py): Recursive implementation of the binary search algorithm.
+- [Binary Search (Iterative)](BinarySearchImple.py): Iterative implementation of the binary search algorithm on a sorted list. Complexity: $O(\log n)$.
+- [Binary Search (Recursive)](BinarySearchRecursiveImple.py): Recursive implementation of the binary search algorithm. Complexity: $O(\log n)$.
 
 ### Heaps
 - [Binary Heap Implementation](BinaryHeapImple.py): Implements a min-heap using a recursive approach, including `insert`, `delMin`, and `buildHeap`.
 
 ### Tree Representations & Traversals
 - [Nodes and References Representation](TreeRepresentationWithNodesReferences.py): A simple implementation of a binary tree using a class-based nodes and references approach.
-- [List of Lists Representation](buildTreeTest.py): Demonstrates building and manipulating a tree using a "list of lists" approach.
+- [List of Lists Representation](BuildTreeTest.py): Demonstrates building and manipulating a tree using a "list of lists" approach.
 - [Tree Level Order Print](TreeLevelOrderPrintImple.py): Prints a binary tree in level order (breadth-first) using a queue, with each level on a new line.