People: Users, Space Users and Organizations
Users lists everyone in the service with their account role, or "External / Space User" for clients. Open a user to see their space memberships, change their account role (Tenant Owners) or Remove User from the service and all its spaces. Invite Team Member (Tenant Owners) sends a team invitation; team invitations grant the Member role.
Space Users manages membership across spaces from one screen. Add an existing user or invite a new one to a chosen space with a chosen role, filter the member list by space, and see each membership's expiry.
Organizations are your client companies. Create one with a name, an optional Owner (the person who can edit it from the portal), contact details and address. On its edit page, register Email Domains, add Members (an existing user, a space user, or an email invitation) and see whether each member joined directly or through a domain. Signature Roles define named signers for an organization, with a primary and backup, which signature templates can resolve automatically.
Organization Domains (from Settings) lists every registered domain with its default role, organization and linked spaces.