text: **Hardware and software**
  
  In the late 2010s, graphics processing units (GPUs) that were increasingly designed with AI-specific 
  enhancements and used with specialized TensorFlow software had replaced previously used central 
  processing unit (CPUs) as the dominant means for large-scale (commercial and academic) machine 
  learning models' training.[126] Specialized programming languages such as Prolog were used in early AI 
  research,[127] but general-purpose programming languages like Python have become predominant.[128] 
  
  The transistor density in integrated circuits has been observed to roughly double every 18 months—a 
  trend known as Moore's law, named after the Intel co-founder Gordon Moore, who first identified it. 
  Improvements in GPUs have been even faster.[129] 