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

In software engineering, the terms "requirement" and "specification" are related but distinct concepts. The main differences between them are as follows:

Requirement: A requirement is a need or demand of a stakeholder that the software must fulfill. Requirements are based on stakeholders' needs and help describe what the software should do. They are abstract and can be thought of as a high-level description of the system's functionality.
Specification: A specification is a detailed and technical document that records the features and behavior of a software system. It provides a clear understanding of the product to be developed and serves as the basis for design, implementation, and verification.

In summary, requirements define the services that a software system must provide and the constraints it must adhere to, while specifications describe the features and behavior of the software system in a detailed and technical manner. A requirements specification addresses the "what" aspect of the software system, and a design specification addresses the "how" aspect.

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

Comparative Table: Requirement vs Specification in Software Engineering

The difference between requirements and specifications in software engineering can be summarized as follows:

Requirement	Specification
Describes the services that a software system must provide, based on stakeholder needs	Provides a detailed and technical description of the software system, including features, behavior, and implementation
Forms the basis of the software and is an important part of the development process	Acts as a document containing analyzed requirements, serving as a bridge between what the business wants and what the technology provides
Can be categorized into various types, such as Functional Requirement Specifications (FRS), Performance Requirement Specification (PRS), and Configuration Requirement Specification (CRS)	Includes tables, diagrams, and use cases to provide a clear understanding of the software system
Helps the development team understand the product they are developing	Used in the design, implementation, and testing phases of software development

In essence, requirements describe the necessary services and functionality of a software system based on stakeholder needs, while specifications provide a detailed and technical description of the software system, including its features, behavior, and implementation.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.