Requirement and Specification
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What is the first thing comes to mind when you hear requirement and specification? Do you see them as separate thing or are they one and the same?
Requirements are what the customer needs (this includes "internal customers"), and, in a perfect world, comprise lots of use cases. Specifications are the technical details of how it should be built, and how it should behave. When it's ready for shipping, met requirements are translated into documented "features", and met specifications are translated into spec sheets/data sheets for the customer.
I wanna be a eunuchs developer! Pass me a bread knife!
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What is the first thing comes to mind when you hear requirement and specification? Do you see them as separate thing or are they one and the same?
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I have always thought that Requirements is what the software needs to do and Specifications is the beginning of how it should do that. The software should be responsive is a requirement. All screens will either respond within 5 seconds or set the wait cursor, is a specification.
Pat O
Your question beautifully illustrates a problem with requirements. I read
The software should be responsive
and was expecting the specification to be "adapts to screen widths from 2048px down to 320px". Just goes to show that even especially as early in the process as requirements collection, it's important to clarify terminology and ensure that all statements are set in an appropriate context that everyone understands. :-)
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What is the first thing comes to mind when you hear requirement and specification? Do you see them as separate thing or are they one and the same?
This is really a confused question. To "specify" something is to "identify (something) clearly and definitely". One can specify a requirement. One can specify a design. One can specify a test. If you want a good example of how things like this are named, research the specifications (and similar documents, like plans or standards) used by the U.S. Department of Defense, or the IEEE, or ISO.
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What is the first thing comes to mind when you hear requirement and specification? Do you see them as separate thing or are they one and the same?
Requirements == needs Specifications == deliverables For every stated need, there is a stated deliverable. A "Correspondence Matrix" shows the relationships.
Need Deliverable Design Code Test
Element Element Element
aN aD aDE aCE aTE
bN bD bDE bCE bTE
cN cD cDE cCE cTE
... ... ... ... ......in theory...
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What is the first thing comes to mind when you hear requirement and specification? Do you see them as separate thing or are they one and the same?
My experience has been that project creep is the great destroyer and ruins both requirements and specifications. :((
A giraffe is a horse designed by a committee--- and executed by an Agile team....
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I like your answer. Though there are fewer company that practice the difference discreetly. I wondered is it because either developers 1. don't understand the difference 2. no allow the opportunity to proper practice 3. Time to market not allows it From my 30 years experience, the more rigorous a well managed team follow process, the faster we can get a product out the door closer to allocated budget.
Requirements are Gathered (From the customer/consumer) Specifications are Written (for the developers) But the lack of either or both, is a MANAGEMENT problem IMO. Now it is either the problem of a bad manager, or a poorly managed process. Tiny projects. You can be a little sloppy. But lets say you are trying to replace the FAA Radar/Plane Tracking systems? (An upgrade that has failed more than once) You get to the point where the exactness of the Requirements "feel" like Specifications, but they are really not. Because they should not be "specifying HOW to get the job done" just what the result is Required to be! These two are separate by definition, IMO
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I agreed. The next question is would you create the requirement separately from the specification or they goes together?
Requirements are one thing; their "feasibility" is another; i.e. Requirements are usually followed up with a "feasibility study" that paint some broad costs and solutions / alternatives which require go / no-go decisions (from management / sponsors). Creating "specifications" otherwise is premature.
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I agreed. The next question is would you create the requirement separately from the specification or they goes together?
The requirements are WHAT. The specification is one HOW out of many possible HOWs. The docs should be kept separately because they are conceptually separate. There might be two ways to do something. Suppose you are building cars, and the customer wants to go 0-60 in six seconds. There are many ways to do this. One way is to built a 4,000 lb car with a turbo-charged six liter V12 producing 700 horsepower. Another way is to build an enclosed four-wheeled bicycle with a 2-stroke engine developing 30 hp. Still a third is motorcycle leathers and a pair of roller skates, plus a small rocket. The collection of requirements may limit you to a single solution of all the solutions you can imagine, but it may not. The organizations that really want to solve problems (like NASA for instance, allow their engineers to explore multiple possible solutions. This doesn't happen much in the software biz, but as competition gets fiercer, it will probably happen more.
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What is the first thing comes to mind when you hear requirement and specification? Do you see them as separate thing or are they one and the same?
A Specification will generally encompass several Requirements.
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What is the first thing comes to mind when you hear requirement and specification? Do you see them as separate thing or are they one and the same?
Just a thought, but might be better to think of the documents as checkpoints along a continuum of vague to detailed. e.g. bid->requirements->specification->design->tests->code. Obviously a lot of effort has to go into properly creating and maintaining these documents which is why many organizations skip over or combine these steps. Or even call them by a different names for emphasis to a given audience. How and why would be well beyond the scope of this reply there lots of different opinions out there on what is really important in the process.
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My experience has been that project creep is the great destroyer and ruins both requirements and specifications. :((
A giraffe is a horse designed by a committee--- and executed by an Agile team....
If you have project creep, then your project should be managed using "agile" technique. Ship the first version of the product when it does something concrete, then update continuously according to the whims of the paying customer. This is one of the great distinctions between waterfall ("design everything up front") versus agile ("start simple and manage the mission creep") styles. With agile, your customer gets something useful sooner and is generally happier in the long run since new ideas and features can be added as part of the plan.
I'm retired. There's a nap for that... - Harvey