apt, to fine-grained file access control and user administration.
Installation
Download the Ubuntu ISO, create bootable media, and walk through the installer for both Desktop and Server editions.
Package Management
Install, update, remove, and search for software using
apt, dpkg, PPAs, and snap packages.ACLs
Set fine-grained file permissions beyond standard Unix ownership using
setfacl and getfacl.Users & Groups
Create and manage user accounts and groups, assign sudo privileges, and control login access.
Ubuntu releases two types of versions: standard releases every six months and Long-Term Support (LTS) releases every two years. LTS versions receive security updates and bug fixes for five years (and up to ten with Extended Security Maintenance), making them the recommended choice for servers and any environment where stability matters.