diff --git a/src/sinefit.py b/src/sinefit.py
index 88ce0fe..aa35174 100755
--- a/src/sinefit.py
+++ b/src/sinefit.py
@@ -1,5 +1,7 @@
 #!/usr/bin/python
 
+# Sine wave fitting.  This runs about 5x faster than realtime on raw data.
+
 import nilmtools.filter
 import nilmdb.client
 from numpy import *