Definition
A filesystem is a method and data structure that an operating system uses to control how data is stored and retrieved on a storage device, such as a hard drive or solid-state drive. It organizes files and directories in a hierarchical structure, making it easier for users and applications to locate and manage information. In practice, the filesystem dictates how data is written to and read from the physical media, translating logical file requests into physical block addresses. Understanding filesystems is crucial for efficient data management, system performance, and implementing security controls like access permissions. For instance, the NTFS filesystem used by Windows manages file permissions and journaling to ensure data integrity. Unlike a simple file allocation table, modern filesystems offer advanced features like snapshots and encryption. This concept is fundamental to domains such as operating systems, storage management, and data security, appearing on exams like CompTIA Security+ and AWS Certified Solutions Architect Associate.