Page Description Diagram

The PDD is a valuable deliverable that can either complement or precede wireframes to negotiate the strategy of the site/pages with clients.

Re-Introducing Page Description Diagrams by Colin Butler, Andrew Wirtanen

Example of a PDD / template

Conceptual Model

A conceptual model is a structured and coherent outline of ideas about how a web site or application will work. It is based on the requirements table and findings from audience and stakeholder research. It can include a model for the content (site map), high level wireframes, user journeys, technical architecture diagrams, and high level style guides.

Benefits in a nutshell

  • explains strategy and core ideas of the envisioned Web site or application
  • helps communicating the ‘big picture’ throughout the development process


Benchmarking is an exercise to determine the performance of a website in comparison with competitor sites. Performance is measured against a set of user experience requirements (disciplines). The score that a website achieves in a discipline is either based on the outcome of specific tasks carried out by users, or on expert opinion, or on a combination of both. The final benchmark report presents the results in a matrix view and graphic charts along with the rationale for the ratings and relevant examples across all disciplines.

    Benefits in a nutshell:

  • Allows to assess performance in relation to other sites
  • Supports evaluating and prioritising requirements
  • Informs user experience design solutions

Heuristic Review

A heuristic review is a systematic inspection of a web-site or application. Usability experts check it against a number of usability standards (‘heuristics’) and determine challenges for successful user-interaction and a rich user experience. A heuristic review can discover up to 70% of user experience problems and is an efficient way of establishing the status quo at the beginning of a project.

    Benefits in a nutshell:

  • Cost effective, quick, and very flexible way to establish user experience challenges
  • Informs evaluation of requirements
  • Informs design of user testing


“A wireframe is a simplified view of what content will appear on each screen of teh final product, usually devoid of colour, typographical styles, and images. Also known as schematics, blueprints, prototypes.”

From: Brown, Dan (2007), Communicating Design, Berkeley: New Riders, p.265

Flow charts (vs. site map)

“Flow charts attempt to visualize a process, usually centered around a specific task or function, For web-based processes, flow charts often represent a series of screens that collect and display infromation to the users. Also known as flows, user flows, process charts.”

“What seperates a flow from a site map is that in the former, time is the defining factor. The relationships between the steps are sequential, not structural or hierarchichal . While site maps capture an information structure that may or may not match the user’s experience of the site, a flow chart defines a process from beginning to end.

From: Brown, Dan (2007), Communicating Design, Berkeley: New Riders, p. 229


“Sitemap is a visual representation of a web site’s structure. Also known as structural model, taxonomy, hierarchy, navigation model, or site structure.”

From: Brown, Dan (2007), Communicating Design, Berkeley: New Riders, p. 199