Pickle is a powerful Python module used for serializing and deserializing Python objects. Serialization is the process of converting a Python object into a byte stream, making it suitable for storage or transmission, while deserialization reconstructs the original object from this byte stream. This functionality is particularly useful in scenarios like saving machine learning models or sharing complex data structures between programs. However, while Pickle offers convenience and flexibility, it also comes with security risks, as unpickling data from untrusted sources can lead to remote code execution vulnerabilities. Understanding its pros and cons is essential for safe usage.