diff --git a/Code/FrequentWords.py b/Code/FrequentWords.py
new file mode 100644
index 0000000..06ef4b2
--- /dev/null
+++ b/Code/FrequentWords.py
@@ -0,0 +1,20 @@
+def FrequentWords(Text, k):
+    words = []
+    freq = FrequencyMap(Text, k)
+    m = max(freq.values())
+    for key in freq:
+        if freq[key] == m:
+            words.append(key)
+    return words
+
+
+def FrequencyMap(Text, k):
+    freq = {}
+    n = len(Text)
+    for i in range(n - k + 1):
+        Pattern = Text[i:i + k]
+        freq[Pattern] = 0
+    for i in range(n - k + 1):
+        Pattern = Text[i:i + k]
+        freq[Pattern] += 1
+    return freq
diff --git a/Notebook.org b/Notebook.org
index 5e37ce7..81ffd9b 100644
--- a/Notebook.org
+++ b/Notebook.org
@@ -21,4 +21,5 @@
     #+end_src 
 
 *** Vocabulary
-      - k-mer: subsquences of length /k/ in a biological sequence 
+      - k-mer: subsquences of length /k/ in a biological sequence
+      - Frequency map: sequence --> frequency of the sequence