diff --git a/slides/12-Iterators-Closures.pdf b/slides/12-Iterators-Closures.pdf
new file mode 100644
index 0000000..9f5097a
Binary files /dev/null and b/slides/12-Iterators-Closures.pdf differ
diff --git a/slides/9-Error-Handling.pdf b/slides/9-Error-Handling.pdf
new file mode 100644
index 0000000..1a2f29a
Binary files /dev/null and b/slides/9-Error-Handling.pdf differ