CPython
CPython is the reference implementation of the Python programming language, written in C. It is the most widely used Python interpreter, responsible for executing Python code by compiling it to bytecode and running it on the CPython virtual machine. It serves as the standard against which other Python implementations are measured and includes the core Python libraries and runtime.
Developers should learn CPython because it is the default and most common Python interpreter, essential for understanding Python's core behavior, performance characteristics, and compatibility with the vast ecosystem of Python packages. It is crucial for general-purpose Python development, scripting, web development (e.g., with Django or Flask), data science (e.g., using NumPy or pandas), and system automation, as most tools and libraries are tested and optimized for CPython.