> For the complete documentation index, see [llms.txt](https://www.pranaypourkar.co.in/the-programmers-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.pranaypourkar.co.in/the-programmers-guide/identity-and-access-management-iam/authentication.md). # Authentication ## About Securing user access to applications and data is more critical than ever. Authentication, the process of verifying the identity of a user or system, plays a foundational role in safeguarding systems from unauthorized access and protecting sensitive information. This verification can take many forms, each tailored to balance security with user convenience. ## Core Principles of Authentication 1. **Identity Verification**: Ensures that the person or entity trying to gain access is authentic. 2. **Access Control**: Grants or denies access based on the authenticated identity. 3. **Security and Privacy**: Protects sensitive data by limiting access to authorized users. ## Categories of Authentication Factors Authentication methods are often categorized by the type of "factor" they use. These factors are based on different forms of verification: * **Something You Know**: Information only the user should know, like a password or PIN. * **Something You Have**: A physical item in the user's possession, like a smartphone, security token, or smart card. * **Something You Are**: Unique biological traits, such as fingerprints, facial features, or retinal patterns (biometrics). * **Somewhere You Are**: Location-based authentication, where access is granted based on the user’s geographic location. * **Something You Do**: Behavioral patterns, like typing speed, rhythm, or swiping patterns on a touch screen. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://www.pranaypourkar.co.in/the-programmers-guide/identity-and-access-management-iam/authentication.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.