diff --git a/rwx/__init__.py b/rwx/__init__.py
index a1c5ee6..ee9f51e 100644
--- a/rwx/__init__.py
+++ b/rwx/__init__.py
@@ -1,3 +1,20 @@
 """Read Write eXecute."""
 
 __version__ = "0.0.1"
+
+
+class Class:
+    """Root class."""
+
+    def __repr__(self) -> str:
+        """Represent object variables.
+
+        :return: representation
+        :rtype: str
+        """
+        name = self.__class__.__name__
+        attributes = [
+            f"{k}={v!r}" for k, v in vars(self).items() if not k.startswith("_")
+        ]
+        arguments = ", ".join(attributes)
+        return f"{name}({arguments})"
diff --git a/rwx/os/abstract.py b/rwx/os/abstract.py
index e985dc5..8b99c28 100644
--- a/rwx/os/abstract.py
+++ b/rwx/os/abstract.py
@@ -3,8 +3,10 @@
 from abc import ABC, abstractmethod
 from pathlib import Path
 
+from rwx import Class
 
-class OS(ABC):
+
+class OS(Class, ABC):
     """Operating System."""
 
     def __init__(self, path: Path) -> None: