diff --git a/src/liballoc/arc.rs b/src/liballoc/arc.rs
index e107d19a87c04..f3b72e4a9ee3f 100644
--- a/src/liballoc/arc.rs
+++ b/src/liballoc/arc.rs
@@ -94,6 +94,9 @@ use heap::deallocate;
 /// With simple pipes, without `Arc`, a copy would have to be made for each
 /// task.
 ///
+/// When you clone an `Arc<T>`, it will create another pointer to the data and
+/// increase the reference counter.
+///
 /// ```
 /// # #![feature(alloc, core)]
 /// use std::sync::Arc;
diff --git a/src/liballoc/rc.rs b/src/liballoc/rc.rs
index e0d7e32ecf504..7cdd488842621 100644
--- a/src/liballoc/rc.rs
+++ b/src/liballoc/rc.rs
@@ -431,7 +431,8 @@ impl<T> Clone for Rc<T> {
 
     /// Makes a clone of the `Rc<T>`.
     ///
-    /// This increases the strong reference count.
+    /// When you clone an `Rc<T>`, it will create another pointer to the data and
+    /// increase the strong reference counter.
     ///
     /// # Examples
     ///