Error Message Guidelines

Summary:
Established wisdom holds that good error messages are polite, precise, and constructive. The Web brings a few new guidelines: Make error messages clearly visible, reduce the work required to fix the problem, and educate users along the way.

The guidelines for creating effective error messages have been the same for 20 years. Good error message should include:

• Explicit indication that something has gone wrong. The very worst error messages are those that don't exist. When users make mistakes and get no feedback, they're completely lost. Email, for example, offers several situations where explicit indication would be useful. Such as: When you send a message that gets eaten by the system and never reaches the recipient. Another good example? When you state in an email that you'll include an attachment, but forget to do so. Finally a job for that annoying paperclip: "You seem to want to attach a file to this message, but you have not done so. Would you like to attach one now?"
• Human-readable language, instead of obscure codes or abbreviations such as "an error of type 2 has occurred."
• Polite phrasing that doesn't blame users or imply that they are either stupid or doing something wrong, as in "illegal command."
• Precise descriptions of exact problems, rather than vague generalities such as "syntax error."
• Constructive advice on how to fix the problem. For example, instead of saying "out of stock," your error message should either tell users when the product will be available or provide a way for users to ask to be notified when the product is restocked.

The Web's most common error message, 404, violates most of these guidelines. I recommend that you write a custom 404 error message instead of relying on the server's built-in "page not found" message.

New Guidelines

The complexity of Web pages has introduced the need for a guideline that wasn't required in the old days. With a DOS interface, users type a command and the error message is displayed on the next line of the TTY. In modern GUIs, users click a command and the error message is displayed in a big dialog box in the middle of the screen, and it doesn't go away until users acknowledge it. On the Web, however, error messages are often hidden as modest text on an overloaded page, leading to a new guideline: Error messages should be

• Visible and highly noticeable, both in terms of the message itself and how it indicates which dialogue element users must repair.

I have frequently observed users make a mistake in a Web form, only to get exactly the same form back from the server with no visible indication of what went wrong. Often, a small error message appeared on the top of the page, but since users look at the page's actionable part first (i.e., the area with the form fields), they don't typically notice the error. A related design flaw is to indicate an error state solely by turning the field label red. This violates one of the oldest and simplest rules for making technology accessible to users with disabilities: Never use color as the only encoding mechanism; always include redundant cues that color-blind users can see.
Two other guidelines can make the error situation less unpleasant for users:

• Preserve as much as the user's work as possible. Let users correct errors by editing their original action instead of having to do everything over again. For example, in presenting search results, show a search box with the user's original query terms to facilitate revisions. If no hits were found, let users search a wider scope with a single click.
• Reduce the work of correcting the error. If possible, guess the correct action and let users pick it from a small list of fixes. For example, instead of just saying "city and zip code don't match," let users click on a button for the city that matches the zip code they entered.

Opportunity to Educate Users

Finally, you probably already know Nielsen's First Law of Computer Documentation: people don't read it. This finding is even stronger for websites, where users truly shy away from any reading that is not essential to their task. Click on Help? Never. Users read system documentation only when they are in trouble (that's the Second Law). They are particularly attentive when they want to recover from an error. Given this, you can use error messages as an educational resource to impart a small amount of knowledge to users. Of course, error messages should be brief and to the point, as should all Web content. However, error messages can still teach users a bit about how the system works and give them information they need to use it better. To further that end, the Web's underlying technology makes another guideline possible:

• Hypertext links can be used to connect a concise error message to a page with additional background material or an explanation of the problem. (Don't overdo this, though.)

program overview

The interdisciplinary program in Internet Technology prepares students for careers in Internet project development and advanced study in information technology or computer science. Students in this program learn about the structure and operation of the Internet in an applied context of web site development, database management and computer programming. They also learn conceptual tools for analyzing and evaluating the Internet, both as a vehicle for information exchange and as a tool of commerce. Majors are frequently involved on projects, as individuals and as team members, in an environment that stresses both theoretical understanding and experiential learning.
Internet Technology majors take courses in a variety of disciplines, including business, computer science, information technology, mass communication, philosophy and psychology, to help develop the full range of skills necessary for success in several web development professions. Two major tracks are available, the standard and the intensive tracks. The intensive track requires more work with formal reasoning and mathematics and delves more deeply into the computer science behind the Internet. Students interested in graduate study are strongly encouraged to pursue the intensive track.
Both major tracks are rich in free electives; eight courses in the standard track, seven in the intensive. Students are encouraged to complement their degree by choosing wisely from courses in accounting, computer science, economics, finance, legal studies, management, marketing, mathematics, mass communication, philosophy, political science, psychology, sociology, and visual communication. Due to overlapping course requirements between programs, minors in business administration, computer science, mathematics and mass communication are easily attainable by adding a small number of courses to the Internet Technology curriculum.
In addition to coursework, students pursuing both major tracks are required to complete an internship or co-op, and a senior project that will be presented to other majors and faculty prior to graduation. The senior project may be prepared in conjunction with the internship or co-op where circumstances permit. Qualifying students may do their internship or co-op in the program's Internet Applications Laboratory, a collaborative learning facility that has developed several internationally recognized Internet projects. To help teach students the skills needed to remain current on Internet Technology, majors are also required to participate in the program's proseminar, a series of regular meetings during which students and faculty make presentations on emerging Internet technologies.
To supplement other majors on campus, the Internet Technology program offers a 21-hour minor that teaches the basic elements of web site design, computer programming, network structure and configuration, and database management. Though generally applicable to most majors at UE, this minor is particularly useful for majors in business, education and mass communication.
Sample Curriculum

First Year
IT 120 Introduction to Internet Applications 3 PSYC 121 Introduction to Psychology 3 World Cultures I 3 American Traditions Elective 3 Elective (Intensive Track: MATH 221 Calculus I) 3/4   15/16	ECON 102 Principles of Microeconomics 3 MATH 134 Survey of Calculus (Intensive Track: MATH 222 Calculus II) 3/4 World Cultures II 3 Creative Dimensions Elective 3 Elective 3   15/16
Second Year
CS 210 Introduction to Computer Science 4 IT 351 Online Media I 3 PHIL 231 Symbolic Logic 3 Foreign Language 111 3 International Perspectives Elective 3 ENGR 90 Co-op/Internship Orientation 0   16	CS 215 Data Structures and Algorithms 3 IT 352 Online Media II 3 MATH 370 Discrete and Combinatorial Math 3 Foreign Language 112 3 Health and Wellness 1 Philosophical/Spiritual Dimensions Elective 3   16
Third Year
IT 310 Internet Networking, Hardware and Software Applications (Intensive Track: CS 475 Networks) 3 MGT 300 Principles of Management 3 Natural Science Elective with Lab 4 Elective 3 Elective 3   16	CS 290 Object Oriented Design and Programming 3 QM 227 Introduction to Statistics (Intensive Track: ENGR 390 Applied Engineering Math) 3 IT 320 Information Modeling, Storage, and Retrieval (Intensive Track: CS 440 Databases) 3 MKT 325 Introduction to Marketing 3 Elective 3   15
Fourth Year
CS 390 Software Engineering 3 IT 444 Information and Technology 3 MKT 470 E-Marketing 3 Technical Elective 3 Elective 3   16	MCOM 485 Mass Communication Law and Ethics 3 IT 490 Information Theory and the Internet (Senior Seminar) 3 Technical Elective 3 Elective 3 Elective 3   15

internet technology

The World Wide Web, scarcely six years old, is already causing significant change. Its scope crosses national boundaries bringing far away places close and altering the very fabric of society. Accessible, two-way interactive information exchange is transforming human relationships in every aspect from economics to expressions of affection.
A high school senior is able to check his school's web site to see what he missed while away on a field trip; then with a few clicks of a mouse, he's listening to the latest release of his favorite recording artist. His little brother checks out the newest toys on the market, making note of what he wants for his birthday. He easily writes Grandma, sending along pictures taken with the family's new digital camera. In a matter of moments, Grandma receives the email from her grandson. She orders gifts in return, checks her investments and applies for a renewal of her driver's license.
The pace of life increases with the speed of transmission, yet, in ways that are easy enough to manage. At the same time, old practices and attitudes are challenged by these transformations creating an environment that is difficult to understand, much less develop with knowledge, foresight and skill.
This makes it clear that the Internet is not a series of computers connected by cable, but a global, interactive system of information exchange. It is as much a form of media as it is a computer network; but even here, it is not media in the traditional sense. Interactivity changes everything. Making good use of the Internet begins with a firm foundation in computer science. But understanding information exchange is also necessary, and this means understanding people and the social structures in which they operate. It also means knowing something about graphic design, information theory, the history of information technology, online law and ethics, and the economic forces that drive technological change.
This explains why the Internet Technology program at the University of Evansville is intentionally interdisciplinary. Knowledge of computers is essential, but successful Internet development requires more.

Boli Muentes’s Composite ARF Tucano

What can I say about this plane. It has seen coverage in a few different magazines. This is the COMP ARF Tucano.
This plane is powered by a Jet Central Turbo Prop. The plane came in at 42lbs Dry. It fly's great. My favorite part of seeing this fly is the smoke system. When you dump the smoke oil into the twin stack you get two smoke trails. Cool to see. I am doing another Tucano that will be finished in Oct of 2010. This one belongs to a friend of mine and I will be able to use it to fly formation with Boli.

RCS 400cc Radial engine with electronic ignition

 

Yes, these are the sweetest engines in all of RC. They look real and they sound real. There is no mistaking the sound. Check out the videos under the videos tabs. If these engines don't give you chills, you need to find a different hobby. They are very reliable as well! You might think with a multitude of pushrods and special ignition that they would be unreliable, but they are not! They take more care and maintenance, but the results are well worth it. Just ask all the top modelers who fly them. We also offer a host of excellent propellers from Biela, TBM, MSC, Mejzlik, PT Models, Xoar and others. We offer 2-blade, 3-blade and even 4-blade props which not only look scale but offer high performance.