Vagrant by HashiCorp is responsbile for setting up development environments under VirtualBox. Vagrant handles all configuration management and makes it easy to share development environments by developers.
Vagrant is no longer recommended as a means of provisioning local development environments. We recommend using Docker Compose instead.
VirtualBox by Oracle is responsible for running Linux Virtual Machines.
Both packages are free and Open Source.
Download and install Vagrant for your OS here: https://www.vagrantup.com/downloads.html
As of this writing, the current version is 1.9.7. You can find out what version of Vagrant you have by running
vagrant --version on the command line. Older versions might have problems.
Vagrant depends on VirtualBox. Make sure you install that first.