diff --git a/docs/markdown/backend/overview.md b/docs/markdown/backend/overview.md
index 0c2092a..35714cc 100644
--- a/docs/markdown/backend/overview.md
+++ b/docs/markdown/backend/overview.md
@@ -2,6 +2,8 @@
 
 Backends are the outputs of the backup process. Each location needs at least one.
 
+Note: names of backends MUST be lower case!
+
 ```yaml | .autorestic.yml
 version: 2
 
diff --git a/docs/markdown/location/overview.md b/docs/markdown/location/overview.md
index 1b3dd96..ccde261 100644
--- a/docs/markdown/location/overview.md
+++ b/docs/markdown/location/overview.md
@@ -3,6 +3,7 @@
 Locations can be seen as the input to the backup process. Generally this is simply a folder.
 The paths can be relative from the config file. A location can have multiple backends, so that the data is secured across multiple servers.
 
+Note: names of locations MUST be lower case!
 ```yaml | .autorestic.yml
 version: 2