option menu
The Option menu contains commands that let you observe and change compiler and development environment options.  To select the option menu, click Option in the menu bar, or press Alt+o on your keyboard.  A menu with the following commands will appear:

Misc  .om  Set miscellaneous options.
ColorTextCursor   .oc Set color of text cursors.
TabWidth   .ot [pixels] Set tab width value.

OptionMisc
Option Misc displays a window containing compiler and PDE options, including bounds checking.

You can turn bounds checking on or off.  Whenever a program is compiled with bounds checking on , extra machine instructions are generated to assure all array accesses are valid.  When your program is running, bounds checking prevents improper array accesses and displays an error message.  Bounds checking intercepts several common errors, including:

  Attempt to access an element in an empty array.
  Attempt to access beyond the upper bound of a dimension.
  Attempt to access data at a node (a higher dimension).
  Attempt to access a node at data (lowest dimension).

Option Misc also lets you toggle:

  the size of text in the PDE between normal and large
  the size of text in the console between normal and large
  the size of scroll bars in the PDE between normal and large
  the size of scroll bars in the console between normal and large
  the color of the console colors between normal and black & white

OptionColorTextCursor
When you select Option ColorTextCursor, a window appears and displays a text cursor and a set of colors you can click to change the color of the text cursor.   Note that the text cursor is not the same color that you click, since the text cursor color is XORed with whatever it's drawn over.  Often selecting medium or light blue will produce a pleasant and easily visible yellow cursor.

OptionTabWidth
By default, tab width in the upper and lower text areas are set every 2nd column, which is best for writing properly structured programs.  But you can use the built-in editor to display and edit text of any kind, so you may want to change tab stops to every nth column.  A column is usually 8 - 12 pixels.

When you select Option TabWidth, a window appears and displays the current tab width value in pixels.  To change the tab width value, change the value and press enter, or click the Set button.