<xsd:simpleType name="families">
    <xsd:annotation>
        <xsd:documentation>The families simple type is a listing of families that OVAL supports at this time.</xsd:documentation>
    </xsd:annotation>
    <xsd:restriction base="xsd:string">
        <xsd:enumeration value="aix" />
        <xsd:enumeration value="apache" />
        <xsd:enumeration value="debian" />
        <xsd:enumeration value="freebsd" />
        <xsd:enumeration value="hp-ux" />
        <xsd:enumeration value="ios" />
        <xsd:enumeration value="macos" />
        <xsd:enumeration value="openbsd" />
        <xsd:enumeration value="oracle" />
        <xsd:enumeration value="os400" />
        <xsd:enumeration value="pix" />
        <xsd:enumeration value="redhat" />
        <xsd:enumeration value="solaris" />
        <xsd:enumeration value="suse" />
        <xsd:enumeration value="windows" />
    </xsd:restriction>
</xsd:simpleType>

• families
• oval:family