Today we live in a capitalist society.
The economy is based on free competition and private ownership of capital.
In other words: All people are responsible for their own well-being and can become rich if they put in enough effort.
This is impossible or even forbidden in other economic systems.
In communism or socialism, for instance, everything should be owned by everyone, roughly speaking.
In capitalist societies like ours, on the other hand, supply and demand determine the price, and everyone strives to acquire possessions and thus wealth.
But this has not always been the case.