Getting data from the various source into one place - Piecing the data together according to the determined setting - Cleaning the data from the noise or erroneous, missing elements - Consolidating data from various sources or data sets into a coherent whole. For example, you have an affiliate advertising network, and you need to gather performance statistics for the current stage of the marketing campaign. - Matching data with the existing data sets. For example, you already have user data for a certain period and unite these sets into a more expansive one; Filtering data through determined settings for the processing. -