diff --git a/histogram.h b/histogram.h
new file mode 100644
index 0000000..0056fc4
--- /dev/null
+++ b/histogram.h
@@ -0,0 +1,10 @@
+#ifndef HISTOGRAM_H_INCLUDED
+#define HISTOGRAM_H_INCLUDED
+
+#include <vector>
+#include "histogram.cpp"
+
+std::vector<size_t>
+make_histogram(const std::vector<double>& numbers, size_t buckets, size_t number_count);
+
+#endif // HISTOGRAM_H_INCLUDED