diff --git a/src/hello-world.md b/src/hello-world.md
index f030d57a..e1c94f51 100644
--- a/src/hello-world.md
+++ b/src/hello-world.md
@@ -33,4 +33,8 @@ Key points:
 * Rust uses macros for situations where you want to have a variable number of
   arguments (no function [overloading](basic-syntax/functions-interlude.md)).
 
+* Macros being 'hygienic' means they don't accidentally capture identifiers from
+  the scope they are used in. Rust macros are actually only
+  [partially hygenic](https://veykril.github.io/tlborm/decl-macros/minutiae/hygiene.html).
+
 </details>