diff --git a/3_RNN/Sigmoid.py b/3_RNN/Sigmoid.py
new file mode 100644
index 0000000000000000000000000000000000000000..eaa7c1ff6ed88cad01faf8202b200eb541f88b56
--- /dev/null
+++ b/3_RNN/Sigmoid.py
@@ -0,0 +1,27 @@
+import numpy as np
+from .Base import BaseLayer
+
+
+class Sigmoid(BaseLayer):
+
+    def __init__(self):
+        super().__init__()
+        self.activation = None
+        self.error_tensor = None
+
+    def forward(self,input_tensor):
+
+        self.activation = 1/(1 + np.exp(-1*input_tensor))
+
+        return self.activation
+
+
+    def backward(self,error_tensor):
+
+        self.error_tensor = error_tensor * (self.activation*(1-self.activation))
+
+        return self.error_tensor
+
+
+
+