LXD vs VirtualBox: What are the differences?
Developers describe LXD as "Daemon based on liblxc offering a REST API to manage containers". LXD isn't a rewrite of LXC, in fact it's building on top of LXC to provide a new, better user experience. Under the hood, LXD uses LXC through liblxc and its Go binding to create and manage the containers. It's basically an alternative to LXC's tools and distribution template system with the added features that come from being controllable over the network. On the other hand, VirtualBox is detailed as "Run nearly any operating system on a single machine and to freely switch between OS instances running simultaneously". VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL) version 2.
LXD and VirtualBox are primarily classified as "Virtual Machine Platforms & Containers" and "Virtualization Platform" tools respectively.
"More simple" is the top reason why over 4 developers like LXD, while over 357 developers mention "Free" as the leading cause for choosing VirtualBox.
LXD is an open source tool with 2.28K GitHub stars and 531 GitHub forks. Here's a link to LXD's open source repository on GitHub.