diff --git a/knowledge base/bash.md b/knowledge base/bash.md
index 5e79d9e..05965b2 100644
--- a/knowledge base/bash.md	
+++ b/knowledge base/bash.md	
@@ -18,6 +18,9 @@
 ## TL;DR
 
 ```sh
+# Logout after 3 minutes of inactivity.
+TMOUT=180
+
 # Declare arrays.
 ARRAY=(
   "first_element"
diff --git a/knowledge base/zsh.md b/knowledge base/zsh.md
index b4734c5..c812bef 100644
--- a/knowledge base/zsh.md	
+++ b/knowledge base/zsh.md	
@@ -51,6 +51,9 @@ Exit files load sequence:
 Aliases are expanded when the function definition is parsed, not when the function is executed. Define aliases **before** functions to avoid problems.
 
 ```sh
+# Logout after 3 minutes of inactivity.
+TMOUT=180
+
 # Quoting.
 "$scalar"
 "${array[@]}"