Breadcrumb navigation (also referred to as a ‘breadcrumb trail’), locates the current webpage in the context of a navigation path.
Aside from the common form, use of the term ‘breadcrumb’ then diverges:
breadcrumb as a presentation format
Navigation displayed in a single-line, suggesting a progression from left to right.
breadcrumb navigation as a dynamic transcript
A visible record of the decisions made by person when moving around a website, similar in function to the browser History.
In addition, topic-path navigation is often presented as a breadcrumb.
The topic-path for this webpage, would be presented in the form of breadcrumb:
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Breadcrumb navigation as transcript/history
Taken literally (and without sophisticated supporting logics to reconcile multiple accesses of a single page, or preserve information hierarchies), breadcrumb-navigation-as-transcript is of little practical use:
Search engines encourage single-page access of websites, in such a case, no additional information can be provided by the breadcrumb.
It is difficult to determine programmatically when a user initiates a new task, and therefore when residual ‘crumbs’ are no longer required.
Transcript-type functionality is already provided by the browser Back button and History (if generally poorly implemented and/or under-utilised by new users).
A form of transcript is of use, however, when navigating a directory-based website. As the user makes a series of selections to find information of increasing granularity, the transcribed breadcrumb illustrates how this content has been classified—a taxonomy.
This classification can help create a mental map of the chosen topic. It also enables the user to retrace their steps to follow a different taxonomic ‘branch’ without needing to re-evaluate the options provided by the formal top-level navigation.
Transcript breadcrumb navigation is also useful when an item is assigned multiple, nonhierarchical classifications, in other words, when there are a number of different, equally valid paths to the same webpage.
Topic path navigation
A topic path shows the location of the current page in context of the website information structure. This form of navigation can help the user visualise how content has been structured, and easily move from a specific-, to broad- content grouping.
Topic path navigation tends to be static rather than dynamic. It shows how the website owner has classified the content, and how the webpage can be relocated using the global navigation, rather than necessarily showing the path the user has taken to reach the page.