  This article reviews the "Once learning" mechanism that was proposed 23 years
ago and the subsequent successes of "One-shot learning" in image classification
and "You Only Look Once - YOLO" in objective detection. Analyzing the current
development of Artificial Intelligence (AI), the proposal is that AI should be
clearly divided into the following categories: Artificial Human Intelligence
(AHI), Artificial Machine Intelligence (AMI), and Artificial Biological
Intelligence (ABI), which will also be the main directions of theory and
application development for AI. As a watershed for the branches of AI, some
classification standards and methods are discussed: 1) Human-oriented,
machine-oriented, and biological-oriented AI R&D; 2) Information input
processed by Dimensionality-up or Dimensionality-reduction; 3) The use of
one/few or large samples for knowledge learning.
