A product description sheet, also known as a product requirements sheet, is a document used during the development process to define what the final product will be. It touches on features, physical/digital design, requirements, and capabilities. Product description sheets are primarily used in waterfall (sequential) workflows, though they can fit into any development structure.
The aim of a product description sheet is to define the scope and purpose of the project early on. This creates a very different process versus “discovery” development, where a loose concept gradually grows into a fully-formed output.
Product description sheets are useful for translating the ideas and goals of the management team into a vision that the development team can execute on. Without a tool like this, it's easy for management to lay out vague ideas that are difficult for the development team to gauge and translate.
The essential ingredients for a product description sheet are:
Product overview: This should explain the goal in creating the product, answering the question: "Why does this product exist?"
Features: This should cover everything the product will be capable of, separated into categories of "should have" and "could have". If a feature is complex, it could be broken into sub-features for added clarity.
Supported systems and environments: This section will list which systems and settings the product will be available on.