According to About.com, sales can account for a part or the whole of a company's revenue. Revenue is the amount of money that a company earns from its primary activities. If a company's primary activity is sales, such as a retail corporation, then revenue is the same as sales. If a company has different revenue streams, such as sales and rental income, then sales accounts for a portion of revenue.
Revenue is typically accounted for on an income statement. Business Case Analysis notes that companies typically have two different revenue columns, one for gross revenue and one for net revenue. Gross revenue is the total amount of revenue for a company over a given period, such as a year or a quarter. For example, if a restaurant sells French fries at $3.00 a piece and sells 1,000 orders over a month, then the gross revenue is $3,000. Net revenue is the gross revenue minus returns, discounts and any allowances that the company gives to customers, such as bulk purchase discounts.
About.com notes that revenue is a very important figure to businesses because it shows whether or not a company is profitable. If a company is a new business, revenue figures can help to estimate future profitability.