Instone (2002) defines and describes three basic types of breadcrumbs: location, path, and attribute.
Location breadcrumbs, according to Instone, are the most common manifestation of this type of navigation on the Web. They denote a page's position in a hierarchy and provide links to pages higher up in the hierarchy. They essentially inform users "where they are" in a site. Participants in Colter's study (2002) referred to the location breadcrumb as a "path they could have taken" to get to a page.
Examples:
Path breadcrumbs are true to the original metaphor as borrowed from Hansel & Gretel. They reflect the path by which the user arrived at the current location. They do not reflect a hierarchy.
Examples:
Attribute breadcrumbs do not necessarily convey hierarchical information. They can be seen on product pages, especially where a product has several attributes. According to Instone, the items in the list may include things such as "subject, price, category, style, and brand." They aid a person in browsing for similar items.
Examples:
These navigational options, all variants on breadcrumbs, each aid a user in a different, albeit valuable way. There exist no clear differences in conventions used while presenting the different types that would easily distinguish them from each other from the user perspective, especially between location and path breadcrumbs. This may lead to user confusion. In a study conducted by Colter et. al. (2002), 5 of 14 participants mistakenly said that the location breadcrumbs they were presented indicated the path they had taken to arrive at their current page.