What is documentation?

Documentation is written information that describes and explains a product, system, or service. It can take many different forms, such as user manuals, technical guides, and online help resources. Documentation is typically used to provide information and instructions to users of a product or service, and to support its development and maintenance.

Internal documentation is documentation that is created and used within an organization, and is typically not intended for external use. It can include things like design and implementation plans, technical specifications, and internal processes and procedures. Internal documentation is often used to help teams within an organization understand and work with a product or service, and to support the development and maintenance of the product or service.

External documentation, on the other hand, is documentation that is intended for use by external stakeholders, such as customers, partners, or users of a product or service. It can include things like user manuals, online help resources, API documentation, and technical guides. External documentation is often used to provide information and instructions to users of a product or service, and to support their use of the product or service.

Both internal and external documentation, when done right, can take your developer experience and user experience to a different level. External documentation is no replacement for a good product. But few good products can succeed in the market without solid documentation.

This is part of an extensive series of guides about software development.

Types of documentation

External documentation

External documentation refers to the written materials that are created for users of a software system. External documentation can be divided into several categories, including:

End-user documentation

This type of documentation is intended for the end users of a software system, who are typically non-technical individuals. End-user documentation includes user manuals, help files, and online tutorials that explain how to use the software and troubleshoot common issues.

Enterprise user documentation

This type of documentation is similar to end-user documentation, but is targeted at enterprise users who are responsible for managing and maintaining the software within their organization. Enterprise user documentation may include information on how to install and configure the software, how to perform maintenance tasks, and how to troubleshoot issues.

API documentation

This type of document is relevant for some products and is aimed at developers who extend the product or interact with it.

Just-in-time documentation

Just-in-time documentation is documentation that is created on an as-needed basis, rather than being included in the software itself. It is often used in situations where the software is highly complex or changes frequently, and traditional documentation may not be sufficient. Just-in-time documentation may include online resources such as FAQs, forums, and wikis, which users can access when they need help with specific tasks or issues.

Related content: read our guide to documentation strategies.

Internal documentation

Internal documentation refers to the written materials that are created for the development team, rather than for external users of a software system. Internal documentation can be divided into several categories, including:

  • Code documentation: Provides detailed information on the components of a software system, and how developers can work with it. It might include any type of information a developer might need to get started with the system, integrate with it, or participate in its development.
  • Process documentation: Describes the processes and procedures that the development team follows when creating, testing, and maintaining software. It may include information on the development methodology, code review process, and testing procedures.
  • Project documentation: Describes the overall goals, requirements, and design of a software project. It may include user stories, acceptance criteria, and technical specifications.

Internal documentation is an important part of the software development process, as it helps the development team understand and follow established processes, communicate effectively with each other, and reference important information about the project and the software.

In the remainder of this article, we’ll primarily focus on internal documentation and how it can help organizations share knowledge and improve software development.

Why is documentation important?

Helps focus on goals

There is a misconception in the development community that a product’s source code should only be documented when it is delivered to customers. However, much of the work of software developers relies on documentation, long before deployment to production.

Documentation starts in the requirements phase of the project. Failure to document requirements can cause a software development team to deviate from original business goals. This is especially evident in agile processes, where goals need to be re-evaluated at the end of each sprint.

Summarizing a set of documented goals significantly improves prospects for the next sprint and allows developers to focus on what matters, learn from mistakes and become more productive.

Mitigate risk from employee turnover

Lack of documentation increases operational risk when existing team members leave a company. When employees leave, they take their expertise with them, often leaving a vacuum that is difficult to fill. By encouraging a culture of documentation, organizations can ensure that even with staff turnover, key technical information remains available and can be used by existing staff and new recruitments.

Related content: read our guide to continuous documentation.

Tracking progress

Agile software development projects are handled by breaking large tasks into smaller chunks called stories. Stories are derived from project requirements and are assigned to developers as tickets or tasks. These tasks are a means of tracking progress, helping to allocate resources and planning future work.

Tasks are a form of documentation in their own right, but can be further enhanced by keeping a comprehensive record of the implementation. Software developers are expected to provide solutions to business problems. Documenting how each task, or group of tasks, was resolved can help the team deal with future issues, and further extend the code that was developed.

Improves feedback and implementation

In agile work methodologies, developers require multiple sprints to complete a software project. The scope of these sprints will change over time and may require reviewing previous sprints and improving deliverables to iteratively build the software.

When related sprints are spaced apart, developers struggle to work on features without documented code, meetings, or daily stand-ups. Reviewing documentation before starting a sprint helps developers plan and schedule implementation. It can also help plan implementation time and costs.

Another aspect is the sprint retrospective—an evaluation of work done at the completion of a sprint. Retrospective documents are also an important part of documentation—they allow teams to get feedback on developer-facing issues, remaining bugs and issues, and features that need improvement.


Without documentation, engineering managers are very limited with assigning tasks – as developers can be assigned to code areas they already know, or they’d have to “pay” with long onboarding time. With documentation in place, engineering managers would have the freedom to assign tasks to various engineers. Of course, if an engineer has worked on a specific part of the codebase they will be the one who knows it best, but everyone on the team should be able to contribute to code with moderate effort.

Internal documentation strategy: what is it and why is it important?

A documentation strategy provides a structure for the company’s technical documentation and the goals it should achieve. Internal documentation strategies typically include knowledge base management, project documentation, design documentation, standard operating procedures (SOPs), and service-related processes.

The following goals are common to most internal documentation strategies:

  • There should be clear and comprehensive information to support each product, project or phase.
  • Documents should be easily available and usable throughout the organization.
  • Documentation content should be clear, relevant, and easy to understand and use.
  • Documentation should support teams in development activity and day-to-day operations.
  • Documentation should focus on things that developers actually need to understand. It should not be written for the drawer.

A documentation strategy should also aim to address challenges like:

  • Good documents that are unused or undiscovered.
  • Poor quality or outdated documents in circulation.
  • Making employees aware of all the documentation relevant to them.
  • Resolving clashes between different document revisions and confusion about which documents to use.

Here are a few key business benefits of an effective documentation strategy:

  • Preversing organizational knowledge is and making it part of “institutional memory”. This promotes a culture of open knowledge sharing.
  • Leveraging the knowledge of insiders who have a deep understanding of software systems and business processes.
  • Promoting efficiency by sharing information and best practices, to avoid duplicate efforts and standardize development practices.

Best practices for creating winning internal software documentation

Determine your target audience

Before starting the writing process, determine the target audience and their end goal. This can differ depending on the specific document, its scope, and the project or product it relates to.

Here are a few steps that can help make a document more relevant to its target audience:

  • Determine the current level of knowledge of the reader.
  • Identify pain points, needs, and common questions readers may have.
  • Determine the most appropriate content delivery format—for example, PDF document, editable wiki article, static knowledge base article.
  • Understand when the reader needs the information, and where they should be able to find it at that time.

Use Markdown

Markdown is a lightweight markup language that can be used to create formatted text from plain text using a specific syntax. It is often used by software developers to quickly create and format code documentation directly in an IDE or text editor, without the need for content authoring tools.

For most developers, writing in Markdown is much easier and faster than using a WYSIWYG editor like Microsoft Word or a specialized documentation authoring tool.

It is especially important to use Markdown, or a similar plain text syntax, when developers are documenting their own software, as Markdown can also support automated documentation as code (DaC) processes and is supported (can appear rendered on) by many development platforms.

Harness the power of visuals

Software documentation can be more compelling, clearer, and more effective with the right visuals. Modern documentation is based on text but uses a mix of images, screenshots, and videos to illustrate key points. While adding visuals to documentation is effective for readers, it also has a high production cost, so may not be feasible for some documentation projects.

Focus on the user experience

User experience is critical for the success of software documentation. Pay attention to elements like:

  • The look and feel of the documentation.
  • How easy it is to navigate and find what the reader needs.
  • Convenient and accurate search options.
  • Responsiveness—readers must be able to properly view the documentation in the devices and browsers they use.
  • Information structure—documents must be structured logically according to topics that are important to the reader.

Implement Continuous Documentation

Continuous documentation is the process of continuously updating previously written documentation as processes or tools change. This is critical to keeping documentation relevant and effective for its target audience.

Development teams constantly tweak, deploy, and test their code, but are often not strongly committed to updating the documentation that accompanies that code. As a result, documentation quickly becomes outdated and irrelevant, losing its value.

Updating documentation regularly can be cumbersome and time consuming. This raises the need for automated documentation tools that can support developers in ensuring documentation always reflects the latest code.

Learn more in our detailed guide to creating software documentation (coming soon).

Automating documentation with Swimm

Swimm treats documentation like code (Docs as code): documentation and code are created and maintained together, and Swimm saves all documentation as code so that your docs are easy to read as Markdown files. Streamlining internal code documentation allows developer knowledge to be shared across teams and repositories.

Swimm’s patented Auto-sync feature automatically keeps code snippets updated with any code changes via GitHub. Swimm then alerts engineering teams when code changes, so you can address your documentation efficiently so that your docs are always synced with your code and accurate.

Learn more about Swimm and sign up for a 1:1 personalized demo.

See Additional Guides on Key Software Development Topics

Together with our content partners, we have authored in-depth guides on several other topics that can also be useful as you explore the world of software development.

Technical Documentation

Authored by Swimm

Code Documentation

Authored by Swimm

Digital Transformation

Authored by NetApp