What Is Functional Specification (FS)?

If you've ever wondered what a functional specification is, wonder no more! A functional specification (FS) describes a specific software product's features and specifications. During the requirements phase of software development, a functional specification is one of the key documents created by a manager or lead developer. The developers should be able to begin the project's design and coding as soon as possible after receiving the functional specification. The FS is an essential part of the software development process because it allows developers to work with precise specifications on what they need to build. The FS can also be used as a reference throughout development by developers and project managers. In software engineering, there's a famous saying: "If you want to write a manual first, you'll end up with a program." It's true. Writing the manual before the product is known serves as an outline for the finished program. Functional specifications include user task descriptions, product comparisons, external interfaces, and compatible hardware, software, framework versions, and operating systems. Nowadays, we're seeing more and more companies adopting this approach to software development—it helps them save time and money by being able to test out their ideas on paper before they start building anything. The functional specification will typically need to evolve as the development of the software product progresses. During the requirements phase, it may be impossible to define all of the screen formats for an interactive program. This is because we don't know how it will be used or how people will interact. We can't say what screens they'll be able to see or what they'll want them to look like until we have an actual working model of the product. Suppose we try to define every single detail at once. In that case, we'll end up having to change things later anyway—but those changes could make our design much more complex than necessary if we had waited until now (when we have all of this knowledge) before making decisions about what things should look like and how they should work. So, if your project has many unknowns at launch time, don't fear! That's normal! Get started with what you know about your project and keep iterating as necessary based on new information that comes along over time—you'll get there!