plothist performs histogram plots,
sending the output to a graphical display or writing it to a file
in some vector or bitmapped graphics format.
You need to supply it with values for one or more sets of X values,
in terms of table columns, and it will bin the data and draw bars
Plot bounds, bin widths etc may be supplied expliicitly, but will be
calculated from the data and set from defaults as appropriate otherwise.
There are many options available to configure the detailed appearance
of the plot, but in its simplest form invocation is quite straightforward.
See Section 8 for more discussion on use of the plotting commands.