Characteristics are used to allow for advanced provisioning rules for FiFo.cloud. They are only available in the Medium and Large package.
Packages that have a given characteristic will only allow machines with this package to deployed on hosts with he same characteristic.
So for example, if you set a characteristic
disk to the value
ssd on one host and
hdd on another you can now create packages that either only deploys on hosts with either SSD or HDDs.