The scientific advance in the use of computers for the replication of human intelligence, or Artificial Intelligence, is unstoppable today. The application of «smart» technology to carry out tasks that, until recently, were performed by lawyers or other staff working in law firms such as well-known paralegals. The development of legal tools based on artificial intelligence is given both for application in law firms, regardless of their size, although with greater impact on large firms. An important consequence is that the use of this technique and the provision of information to clients no longer necessarily have to be carried out by lawyers, since it is the tool itself that prepares the legal information requested. The expression «LegalTech» refers to the application of new technologies to the legal world, developing this work a thorough and comprehensive description of these developments that will change the legal professions. [ABSTRACT FROM AUTHOR]