Krug Chapter 2 How We Really Use the Web and Web Site Design Jeff Offutt https://www.cs.gmu.edu/~offutt/ SWE 205 Software Usability and Design

Users Do Not Read the Web Web page authors want users to study web sites No … users : Glance at a page Scan some text Click on the first link that looks interesting Web page authors … Should not think in terms of telling a story Should think in terms of a sign on a busy highway 21-Nov-18 © Jeff Offutt

Why do we use the Web in the first place? Users Scan Web Pages Why do we use the Web in the first place? To save time Only a few pages get read completely And if they are more than 2 or 3 paragraphs, many users print them Reading paper hurts less than reading screens Very young people don’t notice the pain, but until evolution adapts our eyes to reading screens, everybody over age 25 will prefer reading ink on paper 21-Nov-18 © Jeff Offutt

Humans do not make optimal decisions We Compromise Humans do not make optimal decisions We take the first option that looks reasonable Very few people consider multiple options before making decisions Especially on minor decisions We call people who do “great designers” Why do we compromise ? We’re in a hurry We usually don’t lose much for guessing wrong Comparing options doesn’t lead to better decisions Comparing options is hard work and no fun 21-Nov-18 © Jeff Offutt

We Do Not Understand Fully Few users fully understand a system before they start using it Only engineers … But most software developers expect users to have full understanding Maybe because they are engineers ? Sometimes users come up with interesting ways to use software the designers did not intend Users usually waste time and make mistakes Why ? Learning takes mental effort and time Don’t make me think! 21-Nov-18 © Jeff Offutt

User Success Rate Users only find information they search for on web sites about 42% of the time When given an interactive task, they can only accomplish the task about 26% of the time ! 21-Nov-18 © Jeff Offutt

Home pages should look different from interior web pages Web Site Home Pages Many web sites have a “home page” – the introductory landmark page to the company or organization Home pages should look different from interior web pages No HOME button State purpose of the entire web site Provide a directory of the web site Include a search facility All interior web pages must link to the home page 21-Nov-18 © Jeff Offutt

Do not ask for boolean operators in search Search Boxes More than 50% of users start by searching The search should be in the web site Not the entire WWW Make search available on all pages People do not understand boolean: “I’m interested in SWE 205 and CS 332” should be: 205 OR 332 but most people will enter: 205 AND 332 Do not ask for boolean operators in search 21-Nov-18 © Jeff Offutt

Users do not like to scroll horizontally Screen Width Try not to design to a specific width – keep the HTML as flexible as possible Users do not like to scroll horizontally Put information that is not very important on the right 21-Nov-18 © Jeff Offutt

Unfortunately, we must type and remember URLs URL Design Unfortunately, we must type and remember URLs Help the users avoid typos: Do not use upper case in domain, directory, or file names Underscores require the shift key – hyphens are better, but not much Avoid zeros (0 or O?) and ones (1 or l)? Do not add unnecessary directories Choose short, common words Use standard abbreviations Use URL aliasing to be error tolerant : Allow x.com and www.x.com Provide aliases for common misspellings (jeffoffutt.com and jeffoffut.com) Use the standard “html”, not the non-standard “.htm” Fully specify URLs in HTML links: Do not use this: cs.gmu.edu/~offutt Do use this: https://www.cs.gmu.edu/~offutt/ 21-Nov-18 © Jeff Offutt

Summary Professional HTML designers have accumulated these pearls of wisdom over many, painful, years Standards documents give some of these rules I also want you to understand WHY 21-Nov-18 © Jeff Offutt