What Are Functional Specifications

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    Functional Specifications (based on the Requirement Specifications) describe how something works; what the user will see, what the application will offer, what the finished product will present. The Functional Specifications are written for the manager/supervisor, describing how the application works based on the Requirements document.

    The Functional Specifications (usually created after the Technical Specifications) can be simultaneously created close to the time when the product is almost ready for QA, depending on general practices. Why? Near completion time, the Technical Writer will have a detailed understanding of the finished product and be aware of all the functional changes that occurred during the project life cycle. By that time, the document will be able to describe how the product will function, operate, and behave. In essence, the Functional Specifications will show how the product now truly works.

    It’s not just how it works- it describes how it flows. It will state how one function or activity will present another segment or slice of a product. The Functional Specifications are like mappings which lead you from one section to another. It illustrates or describes the logical flow during a process or procedure.

    It is not a User’s Manual where you are told to click on an icon, tab, or item to be given a screen shot or image of the outcome.

    The Functional Specifications have to:

    • provide if needed, a description of company policies and possibly contact information (depending on the number of company sites),
    • contain a brief introduction highlighting features,
    • include a getting started section describing the system structure, or an applications menu description (i.e., what tool bars will be presented ), and its relevant functions,
    • provide error messages,
    • detail how-to- instructions or procedures, explanations, and activities,( i.e., tabbing leading to what outcome),
    • provide instructions for accessing help , a glossary ,and an appendix with a samples section if needed,
    • indicate what activities cannot be done,
    • how sections, procedures are broken up; the logistics involved,
    • how one process leads to another,
    • describe the circumstances as to when certain events occur or not occur,
    • supply the detailed information for each section and include screen shots, images or process flows, and
    • lastly, provide an evaluation form if desired.

    Functional Specifications also show the history by:

    • explaining the deviations from the original Requirements Specifications,
    • explaining the decision to include or not to include an item in the final product,
    • clarifying why certain decisions were made,
    • describing the environment, and
    • noting the SME’s, Developers, Manages involved.

    Functional Specifications will be presented via:

    • videos,
    • documented instructions,
    • mappings,
    • in-person training, or
    • training tutorials.

    The individual creating the Functional Specifications should be the same individual presenting the Technical Specifications because they are the most knowledgeable about the workings inside and out. In the end, the document like all documents, must speak to the target audience. For Functional Specifications, you have to write to several audiences; make sure you are familiar with all of them before writing. This way, you will know what to emphasize within the document.