Assets are things of value owned by a business including cash, receivables, investments, buildings, land, equipment, vehicles, etc. Liabilities are those amounts the business owes the creditors. They include payables, notes, loans, mortgages, etc. It is also the difference between Assets and Liabilities. Revenue or Income is the money that came into the business from the sale of goods and services.
Income is measured for a period of time.
Cost of Goods Sold is the cost of the product being sold by the business. A service type business will not have a cost of goods sold. Operating Expenses are the daily expenses in running a business. For example, rent, advertising, insurance, etc. However they are a part of doing business such as interest income and expense.