What Is Software Design Document (SDD)?

Software Design Document (SDD) is a document that describes the architecture of a software product. It is one of the primary types of documents in software development. It can be written by a project manager, software developer, or software designer. Ideally, it is a collaborative document created by the whole team. Its purpose is to facilitate the software development process and figure out the way for all team members. A well-thought-out SDD saves time and money. It is a source of information for everyone involved in the development of a piece of software: from clients to technical writers and QA testers. An SDD describes in detail who does what, thus helping all parties to agree upon points at issue.

One of the best ways to write an SDD is to use iterations. This approach allows authors to verify goals and development strategies, collect information more efficiently, and get feedback from all stakeholders. Besides, an SDD is a document that helps them plan their workflow and workload and agree upon their actions in order not to do unnecessary work.

Here are the basic sections of a software design document:

• Title.
• Authors and reviewers.
• Introduction.
• Roles and responsibilities.
• Overview.
• User interface.
• Functions.
• Scope.
• Milestones.
• Glossary.
• References.

As a rule, each company can add other sections to the document or omit some of them, customizing it to special workflows, plans, goals, and needs.

Another piece of advice for those who are going to write an SDD is to use flowcharts, diagrams, screenshots, videos, and mockups to make an SDD as informative as possible.

When should an SDD be written?

• If more than one person is involved in software development
• If you want to create a complex piece of software
• If your software is the only way to generate leads or provide sales

Read more in our post - How to Write a Software Design Document (SDD)