> Python's Buffer Protocol: The #1 Reason Python Is The Fastest Growing Programming Language Today

> The buffer protocol was (and still is) an extremely low-level API for direct manipulation of memory buffers by other libraries. These are buffers created and used by the interpreter to store certain types of data (initially, primarily "array-like" structures where the type and size of data was known ahead of time) in contiguous memory.

> The primary motivation for providing such an API is to eliminate the need to copy data when only reading, clarify ownership semantics of the buffer, and to store the data in contiguous memory (even in the case of multi-dimensional data structures), where read access is extremely fast. Those "other libraries" that would make use of the API would almost certainly be written in C and highly performance sensitive. The new protocol meant that if I create a NumPy array of ints, other libraries can directly access the underlying memory buffer rather than requiring indirection or, worse, copying of that data before it can be used.

(The italic emphasis was copied from the original article.)