Explain business market and consumer market?

Boeing sells aircraft. Individuals are unlikely to buy a B747 (due to lack of space in their garage.. and also because its expensive). The customers of Boeing are companies (airlines). This is a Business to Business (B2B) transaction. The market is known as business market. 

The airline sells tickets to people (consumers). This is a Business to Consumer (B2C) transaction. The market is known as consumer market.