The Tab Size input box is where you to dictate how many characters the cursor will move for each tab stop, between 2 and 16; the default value is 8.

To change the way Borland Pascal displays tabs in a file, just change the Tab Size value to the size you prefer.

Borland Pascal redisplays all tabs in that file at the new size you chose.

You can save this new tab size with the Options│Save Options command.