There are three orchestrator types…
Community - it’s a free version where everyone can use it… limited to two attended bots and 1 unattended bot. It does not have multi-tenancy, but most of the other features are available to use…
Basic - Basic version is limited to 5 attended and 5 unattended robots. This also does not have multi-tenancy
Standard - Includes multi-tenancy and there is no limit for the number of robots we can provision.
These are some of the main differences in these three… However, we can also find a on-prem and a cloud version of this as well.
For more info refer to https://docs.uipath.com/orchestrator/docs/introduction