Economics is a very wide-ranging discipline which is important in the world today for many reasons, including the following.
1. As the number of goods and services available in the world increases, economics helps us to understand how consumers make complex choices between the options available to them.
2. Economics helps us to understand the optimally efficient distribution of resources in society and what mechanisms are most likely to achieve this.
3. At a time of dwindling resources (for instance, fossil fuels), economics provides a mechanism for understanding and dealing with a shortage of raw materials.
4. Economics can provide forecasts of the consequences (and hence the desirability or otherwise) of government intervention in the economy.
5. Understanding the economy helps to provide methods of tackling underlying social problems, such as poverty and unemployment.
6. Economics, by examining consumer choice, can help to explain and predict human behavior in a wide variety of fields, allowing us to prepare for various types of crisis (including economic crisis).
7. Economics helps us to understand the principle of opportunity cost, which is vital for deciding how to use our time and energy.
8. Economics can provide solutions to correct for market failure.
9. The many branches of economics can provide a multiplicity of views of the same situation (which, for instance, could be analyzed from positive, behavioral, and normative perspectives) to give a comprehensive picture of the situation and suggest a range of possible solutions.
10. Economics is an academic discipline which we can apply and even test in our lives on a daily basis, thereby learning how best to allocate our own time and resources.
Although not all the above reasons are exclusive to the modern world, all are certainly applicable in it.