diff --git a/DIRECTORY.md b/DIRECTORY.md
index 08561ba..55dfde8 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -1,19 +1,24 @@
 ## Ciphers
   * [Caesar Cipher](https://github.com/TheAlgorithms/PHP/blob/master/ciphers/caesarCipher.php)
   * [Xor Cipher](https://github.com/TheAlgorithms/PHP/blob/master/ciphers/XORCipher.php)
-  
+## Maths
+  * [Absolute Max](https://github.com/TheAlgorithms/PHP/blob/master/Maths/AbsoluteMax.php)
+  * [Absolute Min](https://github.com/TheAlgorithms/PHP/blob/master/Maths/AbsoluteMin.php)
+  * [Check Prime](https://github.com/TheAlgorithms/PHP/blob/master/Maths/CheckPrime.php)
+  * [Factorial](https://github.com/TheAlgorithms/PHP/blob/master/Maths/Factorial.php)
+  * [Perfect Square](https://github.com/TheAlgorithms/PHP/blob/master/Maths/PerfectSquare.php)
 ## Searching
   * [Binary Search](https://github.com/TheAlgorithms/PHP/blob/master/searches/binary_search.php)
   * [Linear Search](https://github.com/TheAlgorithms/PHP/blob/master/searches/linear_search.php)
-  
 ## Sorting
   * [Bubble Sort](https://github.com/TheAlgorithms/PHP/blob/master/sorting/bubbleSort.php)
   * [Insertion Sort](https://github.com/TheAlgorithms/PHP/blob/master/sorting/insertionSort.php)
   * [Merge Sort](https://github.com/TheAlgorithms/PHP/blob/master/sorting/mergeSort.php)
   * [Radix Sort](https://github.com/TheAlgorithms/PHP/blob/master/sorting/radixSort.php)
   * [Selection Sort](https://github.com/TheAlgorithms/PHP/blob/master/sorting/selectionSort.php)
-
 ## String
+  * [Check Anagram](https://github.com/TheAlgorithms/PHP/blob/master/String/CheckAnagram.php)
   * [Check Palindrome](https://github.com/TheAlgorithms/PHP/blob/master/String/CheckPalindrome.php)
   * [Reverse String](https://github.com/TheAlgorithms/PHP/blob/master/String/ReverseString.php)
   * [Reverse Words](https://github.com/TheAlgorithms/PHP/blob/master/String/ReverseWords.php)
+