DRTV generally bypasses traditional retail stores to make a product sale directly with the consumer, but can also be used to drive product sales at retail. DRTV is comprised of three primary marketing subgroups of short form, long form and live home shopping.
Persia/Persian is more or less synonymous with Iran/Iranian. Persia is just the older name whereas Iran is the country's modern name. I think people from Iran call themselves Persian because of Iran's negative image in the west since the 1979 revolution.
Persians come from the eastern regions of the Middle East. Though modern Iran is officially an Islamic state, the primary religion of ancient Persia was Zoroastrianism. Modern Iran is a country of many different ethnic and tribal groups. Persepolis was the ritual capital of the Persian Achaemenid Empire.