A virtual operating system
Dennis E. Hall, Deborah K. Scherrer, Joseph Sventek · Communications of the ACM · 1980
Moving to a new system is costly and error-prone. The problem can be reduced through use of a virtual operating system that disentangles computing environments from their underlying operating systems. The authors report on their successful experience in doing this and achieving inter-system uniformity at all three levels of user interface: virtual machine, utilities, and command language.