Revenue is an umbrella term that collectively refers to all income that a business incurs. This can include money earned from normal business operations like sales of goods and services (operating revenue) or revenue incurred through side activities like the sale of fixed assets, licensing, or rental income (non-operating revenue).
Once all these expenses are deducted, what’s left is known as net income or net revenue. Operating revenue is a recurring form of income i.e. it is incurred regularly due to ongoing business operations whereas non-operating revenue is rare.