diff --git a/README.md b/README.md
index 43b641e..2febc9c 100644
--- a/README.md
+++ b/README.md
@@ -73,7 +73,7 @@ software in this repository:
 
 ## How it works
 
-The siple idea behind it is that the device does not carry any secret in plain
+The simple idea behind it is that the device does not carry any secret in plain
 text. The passwords are stored on an external SPI flash, encrypted and signed with
 unique keys created when the device is initialized.
 The encryption key is symmetrical (ChaCha) and can be derived on board using the