What does the Text DFM context menu option mean?

When you right click on a Delphi form you get the popup context menu. The bottom option is Text DFM. This option can either be checked or not checked. What does it mean when this option is checked or unchecked?

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Solution

This option is used to select the format used to save your form (in binary or text format).

If you use the text DFM option, the form (dfm file) will be stored in a text format like so

object Form1: TForm1
  Left = 451
  Top = 290
  Caption = 'Form38'
  ClientHeight = 300
  ClientWidth = 635
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'Tahoma'
  Font.Style = []
  OldCreateOrder = False
  PixelsPerInch = 96
  TextHeight = 13
end