Functional Specifications vs. Requirements Document

Question

Currently in my comp., there are some changes going on regarding project documentation. There is a LOT of time and effort spent on discussing functional specs vs. requirements doc. However, I don't think anyone here understands the reason why you would use one over the other. Therefore, I don't understand the difference myself.

Can someone shed some light on this matter please? If you have links to articles, blog posts, etc. That would be helpful too.

Solution 1

A Requirements document should specify the requirements from the perspective of the end user.

User requirements document - Wikipedia

A Functional spec is a level lower and starts to define how different parts of the system should function at the System Engineering level:

Functional specification - Wikipedia

Solution 2

Requirements : “what” the application should do [from user's perspective view]

Functional specification: “how” the application function

Technical specification: “how” the function implemented

Solution 3

Requirement:

You must be in Edinburgh by 2pm tomorrow.

Specification:

Travel by car to the airport ... then take a connecting flight to .... then take the tram to the city centre ... then walk to ....

In general it's 'What's the outcome?' versus 'How are we going to do it?'.

Solution 4

Business Requirement:

Implement a computerized system that calculating employees wages with required deductions and additions and pay the amount the employee is actually owed.

Functional Requirements

• How many employees in the company and their details
• Are they part-time, or full-time or hourly
• What is the pay date
• What is the deductions like TAX, PF, Community Contributions etc

View more solutions