diff --git a/README.md b/README.md
index f284bc8..5098679 100644
--- a/README.md
+++ b/README.md
@@ -15,3 +15,12 @@ python3 caffeine.py
 ```
 
 ## Output
+Caffeine started. Ctrl+C to stop.
+[2026-05-09 10:00:00] F16 pressed #1
+[2026-05-09 10:01:00] F16 pressed #2
+
+Press `Ctrl+C` to stop.
+
+## Why F16?
+
+F16 exists at OS level but isn't mapped to any action in most applications, so it registers as activity without interfering with your work.