Linux permissions control access to files and directories through the owner, group, and others model, using read, write, and execute permissions. Understanding permission strings, numeric values, and special permissions such as SUID, SGID, and the Sticky Bit provides a foundation for understanding Linux access control.
The Linux file system provides the hierarchical structure used to organize files, directories, system configuration, user data, devices, and application resources. Understanding directories, inodes, permissions, ownership, links, mount points, file systems, and storage relationships provides a strong foundation for Linux administration and security.
Linux provides the core operating environment for applications, processes, users, filesystems, services, and system resources. Understanding its architecture, users and groups, permissions, processes, services, and security context establishes the foundation for Linux administration