Question

Choose which of the following are correct sequence for the steps in detail design. 1. user requirement specification 2. software design specification 3. functional design specification?

Answer 1

All these documents/artifacts are part of a SDLC (Software Development Life Cycle) in development of software or a application. 

In SDLC, first step is to understand the scope of the project and document these items in a plain, non-technical English for both business and IT users. These artifacts are usually referred to as Business Requirement Document, or Functional Requirement Document or User Requirement Specification.  This artifacts is written in such a way that it can be easily understood by easily non-technical as well as technical user with same level of comfort. 

From BRD/FRD, next artifact is created which has next level of details such as non-functional requirement, or user interface or database access, or role based privilege, interface such as web services etc. These artifact is usually referred to as Functional Design Specification.

Then comes Software Design Specification. These is the document that has all the technical details that shall be used later to code the application. These are the terms to which IT team has agreed to. These document most often will have the terminology that may not be easily understood by non-technical/non-IT user such as business users. 

So, above sequence would be 1 --> 3 --> 2.