diff --git a/docs/content/routing/routers/index.md b/docs/content/routing/routers/index.md
index 22186a5c0..d9290d28f 100644
--- a/docs/content/routing/routers/index.md
+++ b/docs/content/routing/routers/index.md
@@ -203,9 +203,14 @@ If you want to limit the router scope to a set of entry points, set the `entryPo
 
 ### Rule
 
-Rules are a set of matchers that determine if a particular request matches specific criteria.
+Rules are a set of matchers configured with values, that determine if a particular request matches specific criteria.
 If the rule is verified, the router becomes active, calls middlewares, and then forwards the request to the service.
 
+??? tip "Backticks or Quotes?"
+    To set the value of a rule, use [backticks](https://en.wiktionary.org/wiki/backtick) ``` ` ``` or escaped double-quotes `\"`.
+    
+    Single quotes `'` are not accepted as values are [Golang's String Literals](https://golang.org/ref/spec#String_literals).
+
 !!! example "Host is traefik.io"
 
     ```toml