File Permissions
File permissions are a security mechanism in operating systems that control access to files and directories by defining what actions users and groups can perform, such as reading, writing, or executing. They are fundamental to system administration, data protection, and multi-user environments, ensuring that only authorized entities can interact with sensitive resources. Common implementations include Unix-like systems (e.g., Linux, macOS) with permission bits and Windows with Access Control Lists (ACLs).
Developers should learn file permissions to secure applications, manage server configurations, and prevent unauthorized access in shared or production environments. This is critical for deploying web servers, handling user uploads, scripting automation tasks, and complying with security best practices in DevOps and system administration roles.