# What is AWS Well-Architected Tool?
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AWS Well-Architected Tool (AWS WA Tool) is a service in the cloud that provides a consistent process for measuring your architecture using AWS best practices. AWS WA Tool helps you throughout the product lifecycle by doing the following:
+ Assisting with documenting the decisions that you make
+ Providing recommendations for improving your workload based on best practices
+ Guiding you in making your workloads more reliable, secure, efficient, and cost-effective

You can use AWS WA Tool to document and measure your workload using the best practices from the AWS Well-Architected Framework. These best practices were developed by AWS Solutions Architects based on their years of experience building solutions across a wide variety of businesses. The framework provides a consistent approach for measuring architectures and provides guidance for implementing designs that scale with your needs over time.

In addition to AWS best practices, you can use custom lenses to measure your workload using your own best practices. You can tailor the questions in a custom lens to be specific to a particular technology or to help you meet the governance needs within your organization. Custom lenses extend the guidance provided by the AWS lenses.

Integrations with [AWS Trusted Advisor](https://docs.aws.amazon.com/awssupport/latest/user/trusted-advisor.html) and [AWS Service Catalog AppRegistry](https://docs.aws.amazon.com/servicecatalog/latest/arguide/intro-app-registry.html) helps you more easily discover the information needed to answer AWS Well-Architected Toolreview questions. 

This service is intended for those involved in technical product development, such as chief technology officers (CTOs), architects, developers, and operations team members. AWS customers use AWS WA Tool to document their architectures, provide product launch governance, and to understand and manage the risks in their technology portfolio.

**Topics**
+ [What is AWS Well-Architected Framework?](waf.md)
+ [AWS Well-Architected Tool glossary](definitions.md)

# What is AWS Well-Architected Framework?
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The [AWS Well-Architected Framework](https://aws.amazon.com/architecture/well-architected/) documents a set of foundational questions that enable you to understand how a specific architecture aligns with cloud best practices. The framework provides a consistent approach for evaluating systems against the qualities that are expected from modern cloud-based systems. Based on the state of your architecture, the framework suggests improvements that you can make to better achieve those qualities.

By using the framework, you learn architectural best practices for designing and operating reliable, secure, efficient, and cost-effective systems in the cloud. It provides a way for you to consistently measure your architectures against best practices and identify areas for improvement. The framework is based on six pillars: operational excellence, security, reliability, performance efficiency, cost optimization, and sustainability.

When designing a workload, you make trade-offs between these pillars based on your business needs. These business decisions help drive your engineering priorities. In development environments, you might optimize to reduce cost at the expense of reliability. In mission-critical solutions, you might optimize reliability and be willing to accept increased costs. In ecommerce solutions, you might prioritize performance, since customer satisfaction can drive increased revenue. Security and operational excellence are generally not traded off against the other pillars.

For much more information on the framework, visit the [AWS Well-Architected website](https://aws.amazon.com/architecture/well-architected/).

# AWS Well-Architected Tool glossary
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The following defines common terms used in AWS WA Tool and the AWS Well-Architected Framework.
+ A **workload** identifies a set of components that deliver business value. The workload is usually the level of detail that business and technology leaders communicate about. Examples of workloads include marketing websites, ecommerce websites, the backend for a mobile app, and analytic platforms. Workloads vary in their level of architectural complexity. They can be simple, such as a static website, or complex, such as microservices architectures with multiple data stores and many components.
+ **Milestones** mark key changes in your architecture as it evolves throughout the product lifecycle — design, testing, go live, and production.
+ **Lenses** provide a way for you to consistently measure your architectures against best practices and identify areas for improvement.

  In addition to the lenses provided by AWS, you also can create and use your own lenses, or use lenses that have been shared with you.
+ **High risk issues (HRIs)** are architectural and operational choices that AWS has found might result in significant negative impact to a business. These HRIs might affect organizational operations, assets, and individuals.
+ **Medium risk issues (MRIs)** are architectural and operational choices that AWS has found might negatively impact business, but to a lesser extent than HRIs.

  For additional information, see [High Risk Issues (HRIs) and Medium Risk Issues (MRIs)](workloads.md#wat-hri-mri).