diff --git a/about.md b/about.md
index ccc4e5d7..111e912d 100644
--- a/about.md
+++ b/about.md
@@ -17,7 +17,7 @@ configure. As a consequence, it requires few software dependencies and is
 pre-configured to work out-of-the-box.
 
 Radicale is written in Python. It runs on most of the UNIX-like platforms
-(Linux, *BSD, MacOS X) and Windows. It is free and open-source software.
+(Linux, *BSD, macOS) and Windows. It is free and open-source software.
 
 ## What Radicale Will Never Be
 
diff --git a/tutorial.md b/tutorial.md
index 16080164..3f5fca70 100644
--- a/tutorial.md
+++ b/tutorial.md
@@ -52,6 +52,6 @@ Then launch a command prompt, and type:
 Victory! Open [http://localhost:5232/](http://localhost:5232/) in your browser
 and enjoy the "Radicale works!" message!
 
-## OS X
+## macOS
 
 *To be written.*