Gross Domestic Product is defined as the total production for the country. It is measured by including all the dollars spent to purchase products/services from all the various sellers of goods. The largest purchaser of products/services is consumers. Coming in behind consumers are businesses, remember they are buying goods too. This includes everything from office supplies to the raw materials to make the products the consumers ultimately purchase.
In economics, imports refer to goods and services purchased from foreign nations. In the United States, the number one form of imports is energy (mostly oil). Other top imports include machinery and equipment, electronics and other consumer goods.