Vertical slice

A vertical slice (VS) is a type of milestone, benchmark, or deadline, with emphasis on demonstrating progress across all components of a project.

[citation needed] It may have originated in the video game industry.

It is mostly used in Scrum terminology where the work is planned in terms of features (or stories).

A vertical slice doesn't necessarily affect every component in the software.

For example, if the solution contains a web service, it would live in the same "floor" as the UI, and a feature like "supporting login/logout in webservice" that involves only the web service does not require a change in the UI, but the business and database access layers.