Hartmut Obendorf, Harald Weinreich Faculty for Informatics, University of Hamburg The Look of the Link Concepts for the visualization of extended hyperlinks

Overview Motivation Create a vision  Locate problems  Sketch solutions Conclusion  Systematic UI development  Need for UI guidelines

Motivation for Our Work  Implications for the user interface?  UI aspects were hardly considered  Advanced Hypertext features intrude into the Web

Motivation for Our Work Current Link Interface  Cannot support some of the new features  Is an accidental de facto standard with serious drawbacks, e.g.: –underlined text has reduced readability, –overlapping link markers are not possible, –no standard for links in graphics exists.

Vision Systematically develop the user interface of the Web browsers of tomorrow  Learn from former systems  Consider user interface research  Create prototypes and do usability tests

Vision Departure Destination Arrival Destination Based on Landow‘s “Rhetoric of Hypertext“

Departure Where are the links?  Locate and  Select extended hyperlinks.

Links from different providers Link- base A Link- base B

Link Overload It is known that underlining significantly reduces the readability of text. This is caused by the interference of the underline with descenders, letters like g, f and y. Furthermore, underlining emphasizes text exceedingly. Hypertext stimulates an rather extensive way of reading. Readers often just scan the text for links. This is maybe a symptom of an era in which time seems to be the most valuable good.

Overlapping Markers

Mockup: Departure

Destination Where shall I go?  Information about destination  Selection of destination

Typed Links Semantic link types give a better idea of the target Types can also control the behavior Types are only helpful if displayed or processed XLink  Human readable and computable types  Links, arcs and resources are typed A B

Typed Links B A

Alternative Targets

Mockup: Destination

Arrival Welcome! Where am I ?  Identify target  Understand context

Target Anchors

Co-References

Mockup: Arrival

Conclusion XLink opens many questions – many answers yet to be found Further research and evaluations of hyperlink user interfaces required Don‘t make same mistake again! New developments have to be accompanied by UI considerations