The Python pickle is defined as a module which accepts any Python object and converts it into a string representation. It dumps the Python object into a file using the dump function; this process is called pickling.

The process of retrieving the original Python objects from the stored string representation is called as Unpickling.

Pickling and unpickling are processes in Python used for serialization and deserialization, respectively. Here’s what they involve:

Pickling: Pickling is the process of converting a Python object into a byte stream. This byte stream can be stored in a file or sent over a network. The primary module used for pickling in Python is pickle.
Unpickling: Unpickling is the process of converting a byte stream (previously pickled) back into a Python object. This allows you to reconstruct the original Python object from the serialized data. Unpickling is done using the pickle module as well.

These processes are commonly used for various purposes such as data persistence, sharing data between different Python programs, or even different programming languages (though interoperability might be limited in such cases). It’s important to note that while pickling is a convenient way to serialize Python objects, unpickling data from an untrusted source can be a security risk due to the potential for executing arbitrary code embedded in the pickled data.