Breadcrumb vs Stepper

Both answer “where am I”, but in different spaces. A breadcrumb is spatial: it describes where the page sits in the hierarchy, and it is identical for everyone who lands there, by whatever route. A stepper is temporal: it describes how far through a task you are, and it changes as you go. That is why one is navigation and the other is status. Getting them confused produces the two familiar mistakes — a “breadcrumb” that lists the user's history, which the back button already handles, and a “stepper” whose steps cannot be clicked, which is just a progress bar wearing a costume.

Where this page sits in the site is a breadcrumb. How far through a task you are is a stepper.

Breadcrumb

A trail of links showing the current page's ancestors in the site hierarchy, ending with the page itself.

Reach for it when

The site is deep enough that “one level up” is a question worth answering — docs, catalogues, file browsers.
People arrive from search, straight into level four, with no idea what sits above them.
Sibling and parent pages are worth reaching, and a breadcrumb makes them one click away.
The hierarchy is real and stable. A breadcrumb is only honest if the parent genuinely contains the child.

Avoid it when

The site is flat. Two levels of hierarchy do not need a trail; a single back link is clearer.
You want to show the user's path through the site. That is history, and the back button already owns it.
The page has no single parent — a product in five categories has no honest trail to draw.
It is the only navigation on the page. A breadcrumb supplements orientation; it does not replace a nav.

Stepper

An ordered indicator of the steps in a process, showing which are done, which is current, and which are still ahead.

Reach for it when

A task genuinely has to be split — checkout, onboarding, anything where later steps depend on earlier answers.
The user needs to know the size of the commitment before starting. “Step 1 of 3” is the whole point.
Steps can be returned to, and seeing the earlier ones makes going back obvious rather than a guess.
The order is real. If steps can be done in any sequence, they are sections, not steps.

Avoid it when

The form is short enough to show at once. Splitting eight fields across three screens adds clicks and nothing else.
The number of steps is unknown or changes as you go — a stepper that grows breaks the promise it made.
There are only two steps. That is a form and a confirmation, not a process worth charting.
You want to show hierarchy rather than sequence. That is a breadcrumb.