diff --git a/main.py b/main.py
index 0faf211..518c3c8 100644
--- a/main.py
+++ b/main.py
@@ -7,10 +7,12 @@ TEMPLATE = "template.html"
 games = dict()
 
 def is_submitted(name):
+    """Return True if form element with name was submitted."""
     return request.forms.get(name) != None
 
 @get("/")
 def index():
+    """Drop cookie if it doesn't exist. Redirect to /game/."""
     if request.get_cookie("gameid", secret=KEY) not in games.keys():
         game = Game()
         id = str(max(list(map(int, games.keys()))+[0]) + 1)
@@ -20,6 +22,7 @@ def index():
 
 @get("/game/")
 def show():
+    """Show board. Redirect to index if id given by cookie not in games."""
     id = request.get_cookie("gameid", secret=KEY)
     if id not in games:
         redirect("/")
@@ -27,6 +30,7 @@ def show():
 
 @post("/game/")
 def move():
+    """Catch form submissions and manipulate the game instance."""
     id = request.get_cookie("gameid", secret=KEY)
     valid = True
     if is_submitted("newgame"):