Short definitions for Linux administration, shell, service, storage, and access-control terms.
| Term | Definition |
|---|---|
| systemd | An init and service-management system used by many Linux distributions |
| inode | Filesystem metadata record representing a file-system object |
| ACL | Access control list that extends standard owner, group, and other permission bits |
| SSH | Secure Shell protocol for encrypted remote administration |
| Package manager | Distribution-specific tool for installing, updating, and removing packages |
| Shell script | A text file of shell commands used for repeatable automation |
| LVM | Logical Volume Manager, a storage abstraction based on physical volumes, volume groups, and logical volumes |
| fstab | The /etc/fstab configuration file used by many systems to describe filesystems to mount |
| SELinux | A Linux security architecture that uses mandatory access controls and policy |
| AppArmor | A Linux security module that confines programs with profiles |
See the Linux Administration Quick Reference for common operational checks.