Merge pull request #2587 from bbarker/patch-1

Minor clarification: types -> values in ch16-04

Author: carols10cents

src/ch16-04-extensible-concurrency-sync-and-send.md

@@ -11,7 +11,7 @@ However, two concurrency concepts are embedded in the language: the
 
 ### Allowing Transference of Ownership Between Threads with `Send`
 
-The `Send` marker trait indicates that ownership of the type implementing
+The `Send` marker trait indicates that ownership of values of the type implementing
 `Send` can be transferred between threads. Almost every Rust type is `Send`,
 but there are some exceptions, including `Rc<T>`: this cannot be `Send` because
 if you cloned an `Rc<T>` value and tried to transfer ownership of the clone to