When companies have an influential and controlling investment in another company (defined typically as ownership between 50% and 100%), they will account for their majority ownership using the consolidated method of accounting:
Consolidated simply means that financial reports of the parent company contain all financial information (revenues, net income, etc.) of all businesses in which it holds 50% to 100%.
Since companies often hold a majority ownership of less than 100%, they must eliminate income for minority interests, that is, the minority income belonging to other shareholders, by recording a minority interest expense on the income statement.