as the bulk of the population lacks sufficient discretionary income to purchase the products and services produced by the economy. Examples of emerging technologies Artificial intelligence Artificial intelligence (AI) is the sub intelligence exhibited by machines or software, and the branch of computer science that develops machines and software with animal-like intelligence. Major AI researchers and textbooks define the field as "the study and design of intelligent agents," where an intelligent agent is a system that perceives its environment and takes actions that maximize its chances of success. John McCarthy, who coined the term in 1956, defines it as "the study of making intelligent machines". The central functions (or goals) of AI research include reasoning, knowledge, planning, learning, natural language processing (communication), perception and the ability to move and manipulate objects. General intelligence (or "strong AI") is still among the field's long-term goals. Currently, popular approaches include deep learning, statistical methods, computational intelligence and traditional symbolic AI. There is an enormous number of tools used in AI, including versions of search and mathematical optimization, logic, methods based on probability and economics, and many others. 3D printing 3D printing, also known as additive manufacturing, has been posited by Jeremy Rifkin and others as part of the third industrial revolution. Combined with Internet technology, 3D printing would allow for digital blueprints of virtually any material product to be sent instantly to another person to be produced on the spot, making purchasing a product online almost instantaneous. Although this technology is still too crude to produce most products, it is rapidly developing and created a controversy in 2013 around the issue of 3D printed firearms. Gene therapy Gene therapy was first successfully demonstrated in late 1990/early 1991 for adenosine deaminase deficiency, though the treatment was somatic – that is, did not affect the patient's germ line and thus was not heritable. This led the way to treatments for other genetic diseases and increased interest in germ line gene therapy – therapy affecting the gametes and descendants of patients. Between September 1990 and January 2014, there were around 2,000 gene therapy trials conducted or approved. Cancer vaccines A cancer vaccine is a vaccine that treats existing cancer or prevents the development of cancer in certain high-risk individuals. Vaccines that treat existing cancer are known as therapeutic cancer vaccines. There are currently no vaccines able to prevent cancer in general. On April 14, 2009, The