What is the difference between EDA and Preprocessing?

EDA(Exploratory Data Analysis) as suggested by the name is an initial analysis of the data. Understanding the distributions, getting an idea of the kind of values and their range. It's getting a feel of the data before further analysis and understanding the nature of it. This would ideally give you an idea of the kind of preprocessing it would require which comes after EDA.

Preprocessing is the next step which then includes its steps to make the data fit for your models and further analysis. EDA and preprocessing might overlap in some cases.