diff --git a/doc/lab04-multiprocessing/main.typ b/doc/lab04-multiprocessing/main.typ
index 50c42bc..aa70ef6 100644
--- a/doc/lab04-multiprocessing/main.typ
+++ b/doc/lab04-multiprocessing/main.typ
@@ -2,6 +2,10 @@
 
 = Multiprocessing
 
+== Process, signals, and communication
+
+// TODO Yann
+
 == CGroups
 
 The goal of this part is to understand how to use cgroups to limit the resources of a process. We will initially focus on memory, but cgroups can also be used to limit CPU, I/O, and other ressources.