What is it?
According to the book: Mastering the Requirements Process – Suzanne Robertson and James Robertson. Functional Requirements are the things that your product does to support the work.
In order to describe the product’s functionality, we can use scenarios to help describing.
When writing the requirements description, the most common way is using “The product shall… “, this way it is easier to eliminate semantic confusion. The use of rationale is also recommended to show the reason why the requirement exist. For example, for our Starbucks new product we can describe the requirements like this:
Description: The product shall have local artists’ arts printed in the cups.
Rationale: To be able to satisfy our clients with the designs that they chose in the social media campaign and to support local artists.
A data dictionary is also important in functional requirements, it should contain the definition of the class, each attribute and association.
Avoiding ambiguity is very important when writing requirements.
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To give another example about Functional Requirement description for Starbucks cups design, could be that those designs should be available for all the hot beverages products that Starbucks sales, following the principal model created by designers.
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I guess the data dictionary is an important way to avoid ambiguity!
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