On the desktop side, there is a new theme called “Yaru” that provides a different look and feel than what was provided by default in the prior Ubuntu 18.04 LTS release.
On the server side, Ubuntu 18.10 benefits from an updated Linux 4.18 kernel as well as support for TLS 1.3 encryption. The Ubuntu Server 18.10 integrates the OpenStack Rocky release, providing users with a stable version of the most recent open source OpenStack cloud platform release.
Networking configuration gets a boost in 18.10 as well with netplan.io, which is a network configuration abstraction utility.