The buttons on the left of that card will graph the number of logins, public messages, private messages, DLs, ULs, or BBS usage, depending on which button is 'pushed'. The screen will be cleared, the axis redrawn if necessary, and the left Y axis will be labeled with scaled values.
The right buttons work in a similar way except that the screen is not cleared. Normally the left Y axis values will be used for scale, so that axis will be identical. Up to 5 more graphs can be drawn if the default is used.
If the option key is held down while clicking one the right buttons, the right Y axis will be scaled according to the values of the selected graph. If this option is used, multiple graphs may be misleading since the scales will be erroneous.
The clear button will clear the graph. Holding down the option key will clear the entire screen and the X axis will be redrawn.
The Copy button will copy the entire graph to the clipboard, with labels.
The little button in the botton left corner will 'show' three intermediate fields that are used to contain the graphed values.