Vision Statement
A world where blind and vision impaired people can independently and fully interact with the Windows Operating System and popular third party applications, enabling them to participate in and contribute to society. Blind and vision impaired people are empowered to control their own destiny and ensure this vision, through being able to significantly contribute to the technology that makes this possible. All blind and vision impaired people deserve these rights and opportunities, no matter:- The language they speak
- Their geographic location
- Economic status
- Sensory, physical, cognitive, or mental abilities
Product Description
NVDA (NonVisual Desktop Access) is software that allows blind and vision impaired people to independently interact with the Windows Operating System and popular third party applications by outputting content in either synthetic speech or via a refreshable Braille Display. Developed by NV Access in partnership with a dedicated open source community, NVDA enables blind and vision impaired people to increase their chances at education and employment, and to participate in and contribute to society.Guiding Principles
NVDA’s development follows 16 core principles that shape every decision and feature:1. Freely Available to All
NVDA is free of charge for anyone who needs to access a computer, ensuring availability regardless of economic status.
- Free to download, copy, share, and use on any number of computers
- No cost for future updates
- No barriers to entry based on ability to pay
2. By Users, For Users
Empowering blind and vision impaired people to directly contribute to NVDA ensures it meets their needs.
- Open source project with publicly available source code
- Documentation provided for developers to get started
- The vast majority of contributors are blind or vision impaired users themselves
3. Multilingual
NVDA can be used by people no matter what language they speak.
- Mechanisms for volunteers to translate UI messages and documentation
- Release processes provide time and reminders for translation contributions
- Support for multiple languages and locales
4. Stability
NVDA strives to be stable, minimize freezes, and avoid drastic changes that disrupt user experience.
- Support for breaking changes in Windows or applications before they reach users
- Clear warnings before removing or drastically changing features
- Code designed to recover from application freezes
5. Quality
High-quality, safe code with bugs caught before reaching releases.
- All code reviewed by at least one other core contributor
- Automated unit and system tests
- Alpha and beta builds for early testing by community testers
6. Security
NVDA does not place users at risk of security attacks.
- Priority on eliminating risks of remote control attacks or data leaks
- Strict security report handling process
- Critical fixes minimized in size and complexity
- Optional screen blanking to protect sensitive information
7. Efficient
Responsive to user input while maintaining energy efficiency.
- Use of newer, more efficient APIs with fallbacks for older systems
- Periodic removal of technical debt and code refactoring
- Maintained compatibility with existing scenarios and OS versions
8. Innovative
Pushing boundaries and avoiding stagnation for NVDA and its competitors.
- Prototype new ideas through try builds
- Promotion of idea sharing and healthy debate
- Exploration of cutting-edge accessibility technologies
9. Compliance
App and web developers can rely on NVDA to make best use of implemented accessibility.
- Compliance with all application and web accessibility standards where possible
- Clear documentation of reasoning when unable to comply
- Tools like speech viewer to help developers test accessibility
10. Collaboration
Enabling blind and sighted people to collaborate together.
- Visual highlighting of reading/navigation position
- Speech viewer displays spoken text for sighted collaborators
- Features designed for mixed-ability teamwork
11. Documentation
Users have the knowledge to fully leverage NVDA’s features for productivity.
- Comprehensive, user-friendly documentation
- Official user guide free of charge
- User-level support via community email lists
12. Multimodal
Supporting various modes of interaction to meet diverse needs and preferences.
- Multiple input methods: keyboard, mouse, touch, braille input devices
- Multiple output modes: speech synthesis and braille displays
- All features accessible through all modalities (e.g., deaf-blind users can use NVDA through braille alone)
13. Compatibility
Working with a wide range of software and hardware to ensure users aren’t left behind.
- Regular updates for latest Windows and application versions
- Maintained compatibility with older, officially supported versions
- Support for common speech synthesizers and braille displays
14. Configurable
Users can configure NVDA to suit their particular preferences and tasks.
- Many options for what information is reported and how
- Configurable output attributes (voice rate, pitch, punctuation, braille standard)
- Configuration profiles for easy switching between tasks
15. Extendable
Easily enhanced and customized to meet specific user needs.
- Community-created add-ons for extra features
- Built-in add-on store for browsing and installation
- Broad add-on access to NVDA internals for innovative solutions
- API breakages limited to once per year with advance notice
- Protection against incompatible add-ons with user override option
16. Utility
Providing solutions that serve the blind and vision impaired community.
- Provide utility to a significant proportion of users in day-to-day use
- Are a necessity for a small subset of users, without which NVDA would not be functional for them
How the Vision Guides Development
The vision and principles should always be considered when planning features and prioritizing work. All contributors are expected to keep these principles in mind when making decisions about NVDA’s development.
- Consider which principles the change supports or affects
- Evaluate whether the change aligns with NVDA’s core vision
- Assess the impact on different user groups
- Balance competing principles when they conflict
Contributing Guide
Learn how to contribute to NVDA while following these principles