The column of one-line comments represents the area of the text convenient for insertion of quasi-graphic explanatories to the text of the program. Explanatories can carry as technical, business character, and to serve as reflexion of an emotional condition of the programmer or to express its personal relation to the edited text.
To make quazi-graphic comments conveniently in specialised editors (for example, ASCII Art Studio, ) or to find them in the Internet (for example, on a site ASCII Art Farts). To insert these texts into area of commenting to the right of the basic text of the program to you will help TextLab.
The meaning of all four commands is traditional. Their peculiarity is that they act only on the area of comment, without affecting the main text of the program.