'substitute user， do' ----替代用户, 做----from wikipedia sudo (/suːduː/  or /ˈsuːdoʊ/  ) is a program for Unix-like computer operating systems that enables users to run programs with the security privileges of another user, by default the superuser.  It originally stood for "superuser do",  as that was all it did, and it is its most common usage;  however, the official Sudo project page lists it as "su do".  The current Linux manual pages for su define it as "substitute us