Difference Between Requirement and Specification in Software Engineering

The key difference between requirement and specification in Software Engineering is that a requirement is a need of a stakeholder that the software should address while a specification is a technical document with the analysed requirements. A specification describes the features and behaviour of a software.

Software Engineering is the discipline of developing a software methodically. Requirements are the basis of the software. Requirement gathering and analysing is a major phase of software development. SRS is the document that contains the analysed requirements. Development phases such as designing, implementation use SRS.

CONTENTS

1. Overview and Key Difference
2. What is Requirement in Software Engineering
3. What is Specification in Software Engineering
4. Relationship Between Requirement and Specification in Software Engineering
5. Side by Side Comparison – Requirement vs Specification in Software Engineering in Tabular Form
6. Summary

What is Requirement in Software Engineering?

The entire project depends on requirements. The first step to develop a software is to do a feasibility study. It focusses on technical aspects of the product. Next process is to gather requirements. It is possible by communicating with clients, end users and system users who will use the product at the end. Interview, surveys and questionnaires are main methods of collecting requirements. Finally, analyzing occurs after requirement gathering.

Functional and Non-Functional requirements are two types of this requirement. A requirement that specifies a functional aspect of a software is a functional requirement. Hence, it defines a function of a system or a sub system. Furthermore, a library management system should add, edit, delete and search book details. It should also add, edit and delete member details. Moreover, it should calculate the fine for late returns. Those are few functional requirements of that system. A nonfunctional requirement defines expected characteristics of a software. Security, maintainability, usability, reliability and availability are some examples of nonfunctional requirements. Another type is business requirements. They define the business objectives, vision and goals.

What is Specification in Software Engineering?

First of all, the clients and end-users describe their requirements in natural language. Documenting these requirements happens after analysing. This document is called the Software Requirement Specification (SRS). Then, the system analysts convert them to technical language for the software development team.

This specification works as an agreement between the customer and the development team on what the software product should do. Proper specification helps to prevent software failures. It also helps the development team to get a clear understanding of the product they have to develop.

What is the Relationship Between Requirement and Specification in Software Engineering?

• A specification is a document with analysed requirements.

What is the Difference Between Requirement and Specification in Software Engineering?

Summary – Requirement vs Specification in Software Engineering

The difference between requirement and specification in Software Engineering is that a requirement is a need of a stakeholder that should be solved by the software while a specification is a technical document with the analysed requirements.

Reference:

1.Tutorials Point. “Software Requirements.” Tutorials Point, 8 Jan. 2018. Available here
2.“Software Requirements Specification.” Wikipedia, Wikimedia Foundation, 17 Apr. 2018. Available here   

Image Courtesy:

1.”1538503″ (CC0) via Pxhere