Director — formally appointed as a director of the company, as shown at Companies House.
Control Person — the senior individual who runs the firm day to day. At least one person must be marked as the control person.
PSC — person with significant control: holds more than 25% of shares or voting rights, or otherwise controls the firm.
UBO — ultimate beneficial owner: owns or benefits from 25%+ of the firm, including through other companies or trusts.
Settlor — the individual who originally placed assets into the trust.