diff --git a/README.md b/README.md
index d32df88..b029be5 100644
--- a/README.md
+++ b/README.md
@@ -10,3 +10,7 @@ What we have included so far:
 When working with [Floating-point arithmetic](https://en.wikipedia.org/wiki/Floating-point_arithmetic) we soon realize, that addition is not necessarily [associative](https://en.wikipedia.org/wiki/Associative_property).
 Whenever we need to add numbers with an ever decreasing magnitude to an sum (of the previous numbers) with an ever increasing magnitude, the [Kahan summation algorithm](https://en.wikipedia.org/wiki/Kahan_summation_algorithm) comes in handy and helps keeping the error growth small.
 
+### [window.hh](window.hh)
+
+Some [Window functions](https://en.wikipedia.org/wiki/Window_function)
+
diff --git a/window.hh b/window.hh
new file mode 100644
index 0000000..ef5f7e4
--- /dev/null
+++ b/window.hh
@@ -0,0 +1,57 @@
+/*
+Some window functions
+
+Copyright 2018 Ahmet Inan <inan@aicodix.de>
+*/
+
+#ifndef WINDOW_HH
+#define WINDOW_HH
+
+namespace DSP {
+
+template <int TAPS, typename TYPE>
+class Hann
+{
+	TYPE w[TAPS];
+public:
+	Hann()
+	{
+		for (int n = 0; n < TAPS; ++n)
+			w[n] = TYPE(0.5) * (TYPE(1) - std::cos(TYPE(2) * TYPE(M_PI) * TYPE(n) / TYPE(TAPS - 1)));
+	}
+	inline TYPE operator () (int n) { return n >= 0 && n < TAPS ? w[n] : 0; }
+	inline operator const TYPE * () const { return w; }
+};
+
+template <int TAPS, typename TYPE>
+class Hamming
+{
+	TYPE w[TAPS];
+public:
+	Hamming()
+	{
+		for (int n = 0; n < TAPS; ++n)
+			w[n] = TYPE(0.54) - TYPE(0.46) * std::cos(TYPE(2) * TYPE(M_PI) * TYPE(n) / TYPE(TAPS - 1));
+	}
+	inline TYPE operator () (int n) { return n >= 0 && n < TAPS ? w[n] : 0; }
+	inline operator const TYPE * () const { return w; }
+};
+
+template <int TAPS, typename TYPE>
+class Gauss
+{
+	TYPE w[TAPS];
+public:
+	Gauss(TYPE o)
+	{
+		for (int n = 0; n < TAPS; ++n)
+			w[n] = std::exp(- TYPE(0.5) * std::pow((TYPE(n) - TYPE(TAPS - 1) / TYPE(2)) / (o * TYPE(TAPS - 1) / TYPE(2)), TYPE(2)));
+	}
+	inline TYPE operator () (int n) { return n >= 0 && n < TAPS ? w[n] : 0; }
+	inline operator const TYPE * () const { return w; }
+};
+
+}
+
+#endif
+