Data can be shared through the use of Views. To give a user or group of users access to a View but not its underlying source data, you can share a View to a Space which they have access to.
The ability to share a view to another Space is a particularly useful way to filter out or obfuscate sensitive data before making it available for processing by another set of users. It allows also data owners to create different representations of a given dataset to suppress irrelevant columns or run logical sorting in advance so downstream users can get more immediate value from the data.
You can also export the data from any Dataset in a Space and import it to another Space, either in the same Environment or a different one.