What do you mean by pre processing in KDD?

The preprocessing of KDD is termed as an iterative method of making data prepared for mining. The KDD process steps involve pre-processing and processing stages. The preprocessing steps include assessing the requirements and applications, capturing data, extracting data, cleaning and storing them on a secure server.

Later on, the process begins to transform data using standardization, normalization, and optimisation methods. After that, mining of data takes place. It is to draw patterns or models that could be a good-fit to the application(s). Once found, the testers and data scientists measure patterns and interpret the result. Finally, the knowledge discovery happens for using further in businesses.

Read More:- https://www.eminenture.com/blog/a-simple-guide-to-kdd-process-in-data-mining/