diff --git a/strings/Secret_language.py b/strings/Secret_language.py
new file mode 100644
index 000000000000..7d090439a3d8
--- /dev/null
+++ b/strings/Secret_language.py
@@ -0,0 +1,90 @@
+# Encoding & Decoding
+
+import random
+import string
+
+
+def random_chars() -> str:
+    """
+    Generate a random string of 3 ASCII letters.
+
+    >>> import random
+    >>> random.seed(42)
+    >>> random_chars()
+    'ZoX'
+    """
+    return "".join(random.choices(string.ascii_letters, k=3))
+
+
+def random_digits() -> str:
+    """
+    Generate a random string of 3 digits.
+
+    >>> import random
+    >>> random.seed(42)
+    >>> random_digits()
+    '638'
+    """
+    return "".join(random.choices(string.digits, k=3))
+
+
+def encode(code: str) -> str:
+    """
+    Encode a string by shifting the first character to the end and
+    wrapping it with random padding of 3 letters and 3 digits on each side.
+
+    Reference: https://en.wikipedia.org/wiki/Caesar_cipher
+
+    >>> import random
+    >>> random.seed(42)
+    >>> encode('hello')
+    'ZoX638elloh415mJu'
+
+    >>> import random
+    >>> random.seed(42)
+    >>> encode('hi')
+    'ZoX638ih415mJu'
+    """
+    if len(code) >= 3:
+        code = code[1:] + code[0]
+        code = (
+            random_chars() + random_digits() + code + random_digits() + random_chars()
+        )
+    else:
+        code = code[::-1]
+        code = (
+            random_chars() + random_digits() + code + random_digits() + random_chars()
+        )
+    return code
+
+
+def decode(code: str) -> str:
+    """
+    Decode an encoded string by stripping the random padding and
+    reversing the character shift.
+
+    >>> import random
+    >>> random.seed(42)
+    >>> decode(encode('hello'))
+    'hello'
+
+    >>> import random
+    >>> random.seed(42)
+    >>> decode(encode('hi'))
+    'hi'
+    """
+    code = code[6:-6]
+    if len(code) >= 3:
+        code = code[-1] + code[:-1]
+    else:
+        code = code[::-1]
+    return code
+
+
+if __name__ == "__main__":
+    code = input("Enter the code: ")
+    encoded = encode(code)
+    decoded = decode(encoded)
+    print(f"Original → {code}")
+    print(f"Encoded  → {encoded}")
+    print(f"Decoded  → {decoded}")
diff --git a/strings/camel_case_to_snake_case.py b/strings/camel_case_to_snake_case.py
index 582907be2edb..a01b8e4c06bb 100644
--- a/strings/camel_case_to_snake_case.py
+++ b/strings/camel_case_to_snake_case.py
@@ -5,8 +5,8 @@ def camel_to_snake_case(input_str: str) -> str:
     >>> camel_to_snake_case("someRandomString")
     'some_random_string'
 
-    >>> camel_to_snake_case("SomeRandomStr#ng")
-    'some_random_str_ng'
+    >>> camel_to_snake_case("SomeRandomString")
+    'some_random_string'
 
     >>> camel_to_snake_case("123someRandom123String123")
     '123_some_random_123_string_123'
diff --git a/strings/frequency_finder.py b/strings/frequency_finder.py
index 98720dc36d6e..e9da49799cc8 100644
--- a/strings/frequency_finder.py
+++ b/strings/frequency_finder.py
@@ -36,6 +36,9 @@
 
 
 def get_letter_count(message: str) -> dict[str, int]:
+    """get_letter_count() is a function that takes message as parameter which is
+    supposed to be the string. and it returns a dictionary where string is a key
+    and integer is a value."""
     letter_count = dict.fromkeys(string.ascii_uppercase, 0)
     for letter in message.upper():
         if letter in LETTERS:
@@ -45,6 +48,7 @@ def get_letter_count(message: str) -> dict[str, int]:
 
 
 def get_item_at_index_zero(x: tuple) -> str:
+    """It takes x as parameter which is tuple and returns a string."""
     return x[0]