doc: typo fix
(thanks rod)
@@ -48,7 +48,7 @@ Strings are nodes; ints are nodes; maps are nodes; etc.
[Nodes have their own full chapter of the documentation](./nodes.md).
Operations: some basic computation we can do *on* a node is an operation.
-Traversals and simply updates have built-in functions; more advanced operations
+Traversals and simple updates have built-in functions; more advanced operations
can be built with some use of callbacks.
[Operations have their own full chapter of the documentation](./operations.md).
