diff --git a/.DS_Store b/.DS_Store
index ccb3775..02e540c 100644
Binary files a/.DS_Store and b/.DS_Store differ
diff --git a/Playground.swift b/Playground.swift
index cdcc138..ced05e3 100644
--- a/Playground.swift
+++ b/Playground.swift
@@ -1,7 +1,23 @@
 // https://carrascomolina.com
 import Playgrounds
 
-struct Bike {
+protocol Vehicle {
+    // name ist read-only
+    var name: String {get}
+    var color: String {get set}
+}
+
+struct Train: Vehicle {
+    var name: String
+    var color = "white"
+}
+
+struct ICE: Vehicle {
+    var name = "ICE"
+    var color = "white"
+}
+
+struct Bike: Vehicle {
     var name: String
     var color: String
     // newValue ist ein special keyword
@@ -14,9 +30,10 @@ struct Bike {
 #Playground {
     var greeting = "Hallo Playground"
     var bike = Bike.trek
+    var train = Train(name:"TGV")
     bike.description
     bike.description = "Mein Rad"
     bike.description
-    
+    train
     // write code here
 }
diff --git a/TheSwiftWeek.xcodeproj/project.xcworkspace/xcuserdata/rohing73.xcuserdatad/UserInterfaceState.xcuserstate b/TheSwiftWeek.xcodeproj/project.xcworkspace/xcuserdata/rohing73.xcuserdatad/UserInterfaceState.xcuserstate
index b7e03f7..02f8009 100644
Binary files a/TheSwiftWeek.xcodeproj/project.xcworkspace/xcuserdata/rohing73.xcuserdatad/UserInterfaceState.xcuserstate and b/TheSwiftWeek.xcodeproj/project.xcworkspace/xcuserdata/rohing73.xcuserdatad/UserInterfaceState.xcuserstate differ