Breadcrumbs won't help a site answer users' questions or fix a hopelessly confused information architecture. All that breadcrumbs do is make it easier for users to move around the site, assuming its content and overall structure make sense. That's sufficient contribution for something that takes up only one line in the design.
Breadcrumbs have always been a secondary navigation aid. They share this humble status with site maps. To navigate, site visitors mainly use the primary menus and the search box, which are certainly more important for usability. But from time to time, people do turn to the site map or the breadcrumbs, particularly when the main navigation doesn't quite meet their needs.
Despite their secondary status, I've recommended breadcrumbs since 1995 for a few simple reasons:
- Breadcrumbs show people their current location relative to higher-level concepts, helping them understand where they are in relation to the rest of the site.
- Breadcrumbs afford one-click access to higher site levels and thus rescue users who parachute into very specific but inappropriate destinations through search or deep links.
- Breadcrumbs never cause problems in user testing: people might overlook this small design element, but they never misinterpret breadcrumb trails or have trouble operating them.
- Breadcrumbs take up very little space on the page.
The main argument against breadcrumbs is that many users overlook them. So, why do something that only benefits a minority?
As I've long argued, breadcrumbs are different than most other little-used design elements for the simple reason that they don't hurt users who ignore them.