\a     an ASCII bell character (07)
       \d     the  date  in  "Weekday  Month  Date" format
              (e.g., "Tue May 26")
       \e     an ASCII escape character (033)
       \h     the hostname up to the first `.'
       \H     the hostname
       \n     newline
       \r     carriage return
       \s     the name of the shell, the  basename  of  $0
              (the portion following the final slash)
       \t     the current time in 24-hour HH:MM:SS format
       \T     the current time in 12-hour HH:MM:SS format
       \@     the current time in 12-hour am/pm format
       \u     the username of the current user
       \v     the version of bash (e.g., 2.00)
       \V     the  release  of  bash, version + patchlevel
              (e.g., 2.00.0)
       \w     the current working directory
       \W     the basename of the current  working  direc-
              tory
       \!     the history number of this command
       \#     the command number of this command
       \$     if  the effective UID is 0, a #, otherwise a
              $
       \nnn   the character  corresponding  to  the  octal
              number nnn
       \\     a backslash
       \[     begin a sequence of non-printing characters,
              which could be used to embed a terminal con-
              trol sequence into the prompt
       \]     end a sequence of non-printing characters

PS1="[\u@\h \w]$ "