Before starting any development on Qlik Sense, it is very important to understand the concept of Data modeling. In layman language, you can say that Data modeling is nothing but the way in which different data tables are linked together to get the required analysis. There are various data modeling techniques available, each suited for a specific kind of requirement.
Data modeling is very important for any BI project, because in data modeling you explore the logical relationship between the various attributes of the business. It helps you to visualize the different aspects of the business and find correlation between them. Thus, modeling becomes an important part of BI projects, where business wants to see the correlation between the various attributes and their impact on each other.