The Cray User Group Member Handbook 1990 is a vintage computing document produced by Cray Research in the United States. This handbook likely contains information and guidelines for members of the Cray User Group, providing valuable insights and support for users of Cray supercomputers during that time period. It represents a piece of history from the world of vintage computing, offering a glimpse into the practices and technologies used by Cray Research in the 1990s.