Food, clothing, housing and transportation.

When humans developed to a certain stage, they began to understand the importance of clothing, which is needed by everyone.

The importance of diet is self-evident. You can not play games, go shopping, have no money, no girlfriend and no job, but you can never go without food for a long time. It is the fundamental guarantee for your survival.

The rigid demand industries are supermarkets and medicine.

What is rigid demand? Of course, it is food, clothing, housing and transportation. There are many kinds of goods in the supermarket, which are usually divided according to the characteristics of the goods, such as aquatic products, livestock products, fruits and vegetables, daily processed foods, general foods, daily sundries, household appliances, etc.

Human life is the foundation. You can eat less when you are hungry, but you can't bear it when you are sick. Don't be sick if you have anything, and don't be spiritless if you don't have anything. Now there are many virus infections, especially children with poor resistance, and they can't do without medicine. Therefore, medicine must be a rigid demand!

Routinely needed industries: food (farmers, agricultural production), clothing (textiles, clothing), housing (construction), transportation (cars, transportation), daily necessities (daily necessities, flood control, electricity), medicine (medical treatment).