Whats the difference between firms that provide services and firms that sell products?

Service companies provide services to others regardless of the type of customer and is done as a result of the activity by comparing revenues with expenses and there is no movement of stocks and stocks because it is a service activity

While commercial companies are in the process of selling, buying and importing any commercial operations and is achieved as a result of the sale, purchase and import to obtain a profit from commercial operations and there is a stock in which the supply and disposal of the store

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