diff --git a/cs623/notes.txt b/cs623/notes.txt
index fae9b43..9e12e54 100644
--- a/cs623/notes.txt
+++ b/cs623/notes.txt
@@ -124,3 +124,36 @@ Chapter 4 - Discovery
     - atomic actions - are not broken down into sub-steps
     - plans: sequences and conditions
     - consider task frequencies
+    - textual descriptions:
+    ex: Task Hotel Stay
+      1. select a hotel
+      2. book
+      3. check in
+      4. receive service
+      5. check out
+    ex: Hotel Check-in
+      1. find room
+      2. record guest as checked in
+      3. deliver key
+
+Chapter 5 - Design
+  1. conceptual design
+    - brainstorming
+    - personas - a user profile
+    - scenarios
+    - flowchart - describe the navigational structure
+    - cognitive walkthroughs
+      - an evaluation technique
+      1. step through the action sequence for a task
+        - role playing
+      2. check it for potential usability problems in design
+        - story telling
+      what you need
+        1. a conceptual model or prototype
+        2. a task description
+          - list of actions
+      questions to ask
+        1. is the action helpful for the user's goal?
+        2. is the action visible to the user?
+        3. does the user know how to proceed?
+        4. is the feedback sufficient?