GRAPHICAL USER INTERFACE GITAM GADTAULA

OVERVIEW What is Human Computer Interface (User Interface) principles of user interface design What makes a good Interface Why should we care about UI?

WHAT IS UI? Visual part of computer application or operating system through which a user interacts with a computer or a software. It determines how commands are given to the computer or the program and how information is displayed on the screen. Three main types of user interfaces are : 1.Command language: The user must know the machine and program- specific instructions or codes. 2.Menus: user chooses the commands from lists displayed on the screen. 3.Graphical user interface (GUI): user gives commands by selecting and clicking on icons displayed on the screen.

THE USER INTERFACE System users often judge a system by its interface rather than its functionality A poorly designed interface can cause a user to make catastrophic errors Poor user interface design is the reason why so many software systems are never used Most users of business systems interact with these systems through graphical user interfaces (GUIs) In some cases, legacy text-based interfaces are still used

WHY IS GUI NEEDED? They are easy to learn and use. Users without experience can learn to use the system quickly. The user may switch quickly from one task to another and can interact with several different applications. Information remains visible in its own window when attention is switched. Fast, full-screen interaction is possible with immediate access to anywhere on the screen

SOME GUI TOOLS

USER INTERFACE ETHICS All resources have users or potential users. Jef Raskin, The Humane Interface (2000): laws of interface design: A computer shall not harm your work or, through inactivity, allow your work to come to harm. A computer shall not waste your time or require you to do more work than is strictly necessary.

ADVANTAGES OF GUI It can be user-friendly and speed up the user's work. It can be more attractive for non-technical people. In general, it looks more professional (but this does not mean it is always the best solution).

GUI DISADVANTAGES When it is not properly built, it can be very difficult to work with.

GUI DISADVANTAGES It generally requires more memory resources than a non-graphical one. It might require the installation of additional software, e.g., the "runtime environment" in the case of java or some other platform.

MENU DRIVEN INTERFACES This type of interface lets you interact with a computer or device by working your way through a series of screens or menus.

MENU DRIVEN INTERFACES Think about your iPod or mobile phone, they both use a menu driven interface. You are presented with a menu, you make a choice and then the next menu appears on the screen. You make another choice and so on.