What I learn from .018 : Coursera course : Usable Security

Ages ago. I enrolled myself into course Usable Security on Coursera. 

    It was about usability and Human-Computer Interaction related to security. If you are interested in UX.  I highly recommended this course.
Sadly, I lost some of my notes, but this is what I still remember from  I learned from this course:

1. Human-Computer Interaction (HCI) is a study how people interact with technology.
2. Tasks are goals that users set out to accomplish when they are using the system. 
3. To evaluate the usability of the system, you need to create a representative list of tasks and evaluate the usability of those tasks according to following factors:
1. Speed (how quickly task can be accomplished)
2. Efficiency (how many mistakes are made in accomplishing the task)
3. Learnability (how easy is to learn to use the system)
4. Memorability (once learned, how easy is to remember how to use the system)
5. User Preference (what do users like?)
4. Tasks.. 
1. should NOT  be leading or descriptive (shouldn't have instructions what to do step by step)
2.  should NOT be too specific (shouldn't say like third link )
3. should NOT be a focus on least important  or rare elements than users will do (like checks list of authors of the website)
5. Mental models
1.  let understand how users perceive systems.
2. are used our experience and/or knowledge from all other parts of our life to  interact with new things. 
3. are important to understand as If we take these mental models into account when we're design software, we can build things that will be easier learn, remember and easier to use faster and more efficient.
6. A mental model is a combination of:
1. Affordances  (Affordances are things within a system that show a user how they're supposed to be used. 
2. Mapping
3. Visibility
4. Feedback
5. Constraints (how a system can prevent us from doing things that we shouldn't and how the design of it can encourage us to do things the right way.
7. There are much more to learn from this course but I forgot it already.

Conclusion

    It is a great course for people who are interested in UX. It is worth spend some time on readaing about basics of cognitive psychology and learn how memory works as It will help you learn much more from this course.