Chapter 12: Text

1. The Resonant Interface HCI Foundations for Interaction Design First Edition by Steven Heim Chapter 12:Text

2. Chapter 12 Text • Human Issues Concerning Text • Using Text in Interaction Design • Technical Issues Concerning Text

3. Chapter 12 Text • Human Issues Concerning Text • The Reading Process • The Reading Purpose • Paper versus Screens • Importance • Most Common • Last Resort • Goal: Make Text as Readable as Possible

4. Human Issues Concerning Text • The Reading Process • Saccades: Quick, jerky movements • Fixations: Intermittent pauses on areas of interest • Visual and cognitive processing occurs during fixation but not during saccades. • If text is difficult to comprehend, if it includes long or unfamiliar words, fixations increase in duration • Short: legibility; Long: comprehension

5. Human Issues Concerning Text • The Reading Process Experienced readers recognize word shapes not as an ordered sequence of letters. Capital letters for (1) text entry (2) distant text.

6. Human Issues Concerning Text

7. Human Issues Concerning Text

8. Human Issues Concerning Text • The Reading Process We read extended text passages more quickly in lowercase than uppercase • Lowercase presentation is more common • Lowercase words have more distinctive shapes

9. Human Issues Concerning Text • The Reading Purpose • Continuous process (novel) • Scanning • Reading from screens or paper

10. Human Issues Concerning Text • Paper versus Screens Paper is more flexible than electronic media We often rely on our spatial memory when we search for information Place holders

11. Human Issues Concerning Text

12. Human Issues Concerning Text • Paper versus Screens The ability to annotate aids comprehension

13. Kindle Highlight

15. Chapter 12 Text • Using Text in Interaction Design • Commentary/Instrumental • Legibility • Readability • Physical Factors

16. Using Text in Interaction Design • Commentary – Text that informs • The most common form is help text • Contextual help provides immediate assistance to users without requiring them to leave the context in which they are working, such as pop-up menus. • Procedural help provides the steps necessary for carrying out a task. • Reference help serves as an online reference book. • Conceptual help provides background information, feature overviews, or processes.

17. Using Text in Interaction Design • Instrumental – Text that does work (Ramey, 1989) • Controls: the control’s function and its label are viewed as one entity • Buttons • Checkboxes • Radio Buttons • Icons • Hyperlinks

18. Using Text in Interaction Design • Hypertext Hypertext links must give unambiguous indications of the target destination • Krug - Don’t Make Me Think (2006) - suggests that what is important is not so much the number of links that a visitor must click but rather the quality of the links

19. Using Text in Interaction Design • Legibility Legibility is an essential first step in the reading process • We must take these environmental conditions into consideration when we are making determinations about font size and foreground/background contrast. Design for the least favorable conditions

20. Using Text in Interaction Design • Legibility • We must also consider age and possible vision impairments Our capacity to perceive details decreases with age

21. Using Text in Interaction Design • Readability • Comprehension is affected by: • Line length • Line spacing • Formatting • Margin width • Scrolling • It is also affected by grammatical issues, such as semantics and syntax

22. Using Text in Interaction Design • Readability Use the terms people will see in the interface Technical terminology should be avoided Word-for-word translations can create confusion

23. Using Text in Interaction Design • Readability – Ambiguous text Avoid noun stacks; they are ambiguous • Linguistic “Escher effects” (Ramey,1989) • Input Mode • Search Results

24. Using Text in Interaction Design • Physical Factors • Font size • Line length • Margin width • Vertical line spacing • Alignment • Contrast • Scrolling versus paging

25. Using Text in Interaction Design • Font size • Factors that affect font size: (Horton, 1994) • Reading Distance—Greater distances require larger text. • Screen Resolution—Smaller text requires greater resolution to keep the characters clear and legible. • Text/Background Contrast—Negative contrast is optimal (black type on a white background). • Visual Acuity of User—Not all users have 20/20 vision. • Type of Reading—Text can be scanned, read word by word, or read character by character

26. Using Text in Interaction Design • Font size • General benchmarkformula for font size, given normal vision and optimal conditions Font Size = 2d(tan(/2)) X DPI

27. Using Text in Interaction Design • Line length Line length affects reading performance but not comprehension Lines of greater length are read more quickly People prefer medium line lengths

28. Using Text in Interaction Design • Margin width • Shorter lines—4 inches—with large margins increased reading performance (Youngman and Sharff, 1998) • Maximal use of white space

29. Using Text in Interaction Design • Vertical line spacing • The spacing between lines of text (single spacing, double spacing, etc.) is called leading • Double spacing has been shown to improve reading speed (Kolers, Duchnicky, & Ferguson, 1981) • It might necessitate a smaller font size to increase the amount of visible information per screen

30. Using Text in Interaction Design • Alignment For optimal reading of lengthy texts, right and center alignments should be avoided Text should also be considered a graphical component of a page

31. Using Text in Interaction Design • Contrast Contrast sensitivity decreases significantly with age

32. Using Text in Interaction Design • Color Contrast • Because black and white have the highest contrast the addition of any color will reduce the contrast Luminance contrast is more significant than color contrast

33. Using Text in Interaction Design • Scrolling versus paging Paging Scrolling Consistent link location.

34. Using Text in Interaction Design • Scrolling versus paging Scrolling facilitates maintenance and printing The choice of paging versus scrolling depends on task and layout

35. Chapter 12 Text • Technical Issues Concerning Text • Components of Digital Text • Web Text • Globalization/Localization • Dynamic Text Presentation

36. Technical Issues Concerning Text • Components of Digital Text • Character Set = Character Repertoire + Character Codes + Encoding Scheme • ½ Comes from the individual glyphs‘1’, ‘/’, and ‘2’ • ASCII

37. Technical Issues Concerning Text • ASCII • Basic ASCII uses 7-bit encoding, which allows it to represent 128 characters. • Including alphanumeric and some nonprinting characters such as line feed and carriage return • ASCII was extended to 8 bits, allowing for 256 characters

38. Technical Issues Concerning Text • Unicode The Unicode Consortium is a non-profit organization originally founded to develop, extend and promote use of the Unicode Standard, which specifies the representation of text in modern software products and standards. The Unicode Standard is a character coding system designed to support the worldwide interchange, processing, and display of the written texts of the diverse languages and technical disciplines of the modern world. In addition, it supports classical and historical texts of many written languages. (Unicode Consortium)

39. Technical Issues Concerning Text • Unicode • 8-bit • 16-bit • 32-bit • Most web pages use Unicode • Still a work in progress

40. Technical Issues Concerning Text • Fonts Serif Sans serif Cursive Cursive text requires high-resolution screens • Variable-width font ioioioioio • Fixed-width font ioioioioio

41. Technical Issues Concerning Text • Fonts

42. Technical Issues Concerning Text • Web Text • Structure • Presentation • Web Fonts • Hypertext

43. Technical Issues Concerning Text • Web Text – Structure • HTML elements are used to create the structure of a web page <title>Company Name—Area of Site—Specific Page</title> <h1> Topic #1</h1> <h2>Sub-topic #1</h2> <h2>Sub-topic #2</h2> <h3>Sub/Sub-topic #1</h3> <h1>Topic #2</h1> <h2>Sub-topic #1</h2> <h2>Sub-topic #2</h2>

44. Technical Issues Concerning Text • Web Text – Presentation • Cascading Style Sheets (CSS) are used to create the presentational aspects of a web page • Some markup elements have inherent presentational qualities. • Styles must be appropriate for the markup elements to which they are assigned. • Styles must be derived from and serve to clarify the content. • Styles should not compete with the content. • Styles should not conflict with user’s expectations.

45. Technical Issues Concerning Text • Web Fonts • We can use the CSS font-family property to specify a particular font – it must reside on the user’s computer • Times New Roman and Arial are the most prevalent • At low point sizes, serif fonts suffer reductions in legibility • Georgia, Verdana, and Trebuchet maintain legibility at small sizes and have been designed to facilitate reading on the Web

46. Technical Issues Concerning Text • Hypertext • Hyperlinks have three states • Normal – blue • Active – red • Visited – purple Hypertext links at Useit.com

47. Technical Issues Concerning Text • Hypertext Hyperlinks must be obvious • CSS can be used to change the color of hyperlinks • There are four possible states a:link { color: red } /* unvisited links */ a:visited { color: blue } /* visited links */ a:hover { color: yellow } /* user hovers */ a:active { color: lime } /* active links */

48. Technical Issues Concerning Text Hover and active links on the Amazon.com Web site Side navigation links

49. Technical Issues Concerning Text Hypertext links at the W3.org Web site Nonfunctional hyperlink Visited link

50. Technical Issues Concerning Text • Globalization/Localization • Direction (Character and line sequences) • Alignment and Space (Translation) • Collating sequences (Difference in alphabets) • Delimiters (Tokenization and Segmentation) • Diacriticals (Change meaning)