The border in the text mode can be drawn using simple symbols or using pseudographics. Using the BorderType property it is possible to choose the mode of border drawing. It may have the following modes:

Simple - drawing a border using simple symbols such as  "+", "-", and "|";

UnicodeSingle - drawing a border using the symbols of  pseudographics; symbols of solid border are used;

UnicodeDouble - drawing a border using  the symbols of  pseudographics; symbols of double border are used.