diff --git a/main.py b/main.py
index 2dbb044..8807fc8 100755
--- a/main.py
+++ b/main.py
@@ -1,5 +1,9 @@
 #!/bin/python3
 
+# bookmarks
+# 
+# threading: https://stackoverflow.com/questions/9848464/how-to-listen-to-http-requests-and-a-serial-channel-in-the-same-python-program
+# wait for serial input: https://stackoverflow.com/questions/13017840/using-pyserial-is-it-possible-to-wait-for-data
 import serial
 import time
 
@@ -7,7 +11,6 @@ ser = serial.Serial('/dev/ttyACM0', baudrate = 9600, timeout = 1)
 
 #time.sleep(3)
 
-# https://stackoverflow.com/questions/13017840/using-pyserial-is-it-possible-to-wait-for-data
 
 while 1:
     # {  "command": "switch",  "arg": "one",  "state": "off"}