All companies that you have relations with are stored as organizations. These can be customers and suppliers for your company, or other relevant organizations.
Organizations should be entered in VOGSY once they become qualified leads: there is serious interest from the organization in doing business. You can add team members an organization to manage this proces and work towards getting a project.
If you create opportunities or projects for an organization, they will be linked to that organization and a contact person. The details of one or more contact persons at this organization can be added separately.