Deep learning models are part of a larger data analysis pipeline. This pipeline includes data collection (ensuring representativeness and avoiding bias), cleaning (handling missing data, irrelevant features, and inconsistent dimensions), numerical encoding (transforming data for neural network input), model training, post-processing (decoding outputs, assessing confidence), and validation using held-back data. Each stage is crucial for successful real-world application. This segment details the crucial initial stage of data collection in a machine learning pipeline, emphasizing the need for sufficient, representative data that avoids biases and includes important outliers. The example of a self-driving car needing to recognize an Amish buggy highlights the real-world consequences of data set limitations and the importance of careful data collection to ensure model accuracy and safety. This segment explains the critical step of numerically encoding data for neural network input. It contrasts the straightforward encoding of image data with the challenges of text data, introducing the concept of data transformation to improve model performance. The example of transforming Cartesian coordinates to polar coordinates illustrates how changing data representation can create clearer linear decision boundaries for better classification. This section focuses on the essential data cleaning process before model training. It covers handling missing data, removing irrelevant features (like patient IDs), and addressing inconsistencies in data dimensions across different examples, using the example of image processing with varying resolutions. The discussion highlights the importance of preparing data for effective model training.