Once data requirements are defined, the next step is identifying where the data will come from. Data sources are generally categorized into internal and external sources. Each type offers unique advantages, challenges, and use cases. Understanding available sources ensures that models are comprehensive, reliable, and relevant.
Internal Data Sources
Internal sources are all data generated within the organization. This includes databases, CRM systems, operational records, logs, and financial documents. Internal data is often the most valuable because it directly reflects the company’s customers, operations, and performance.

External Data Sources
