diff --git a/README.md b/README.md
index 9e82dd898..3c173b24c 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # dump1090-fa Debian/Raspbian packages
 
-dump1090-fa is a ADS-B, Mode S, and Mode 3A/3C demodulator and decoder that
+dump1090-fa is an ADS-B, Mode S, and Mode 3A/3C demodulator and decoder that
 will receive and decode aircraft transponder messages received via
 a directly connected software defined radio, or from data provided over a
 network connection.