Summary -
In this topic, we described about the below sections -
A comment line is any line that starts with comment character (*, /) in column-7 or starts with character string *> in the program text area (either in Area-A or Area-B).
A comment line can have a floating comment indicator (*>) as the first character-string in the program text area (either in Area A or Area B).
For example -
----+----1----+----2----+----3----+----4----+----5----+----6----+----7--
01 WS-VAR PIC X(12). *> INLINE COMMENT in Area-B
*> INLINE COMMENT starts in Area-A
A comment line can be created with a combination of any allowed computer characters. i.e, A-Z, a-z, 0-9, and all computer-supported characters.
For example -
----+----1----+----2----+----3----+----4----+----5----+----6----+----7--
* daakfa;kfaf *&%$#2)() - Valid Comment
Comment lines can be placed anywhere in a program.
For example -
----+----1----+----2----+----3----+----4----+----5----+----6----+----7--
* THIS IS COMMENT1
DATA DIVISION.
WORKING-STORAGE SECTION.
* THIS IS COMMENT2
PROCEDURE DIVISION.
* THIS IS COMMENT3
Each comment lines must begin with an asterisk (*) or a slash (/) in the indicator area, or with a floating comment indicator (*>).
For example -
----+----1----+----2----+----3----+----4----+----5----+----6----+----7--
* FULL LINE COMMENT WITH * IN COLUMN-7.
/ PRINTER ESCAPE LINE COMMENT .
DATA DIVISION.
WORKING-STORAGE SECTION.
01 WS-VAR PIC X(12). *> INLINE COMMENT
The compiler treats a comment line as documentation and does not check for syntax errors.
Practical Example -
Scenario - Below example describes how the comments added in COBOL programming.
Code -

----+----1----+----2----+----3----+----4----+----5----+----6----+----7--
***************************** Top of Data ******************************
IDENTIFICATION DIVISION.
PROGRAM-ID. COMMENTS.
AUTHOR. THE PROGRAM WRITTEN BY MAINFRAMESTECHHELP FOR
EXPLAINING ABOUT COMMENTS IN DETAIL.
INSTALLATION. 01-JAN-2000.
DATE-WRITTEN. 11-MAY-2021.
DATE-COMPILED. 11-MAY-2021.
SECURITY. NORMAL.
DATA DIVISION.
WORKING-STORAGE SECTION.
* FULL LINE COMMENT WITH * IN COLUMN-7.
/ FULL LINE COMMENT WITH / IN COLUMN-7.
01 WS-VAR PIC X(12).
PROCEDURE DIVISION.
* FULL LINE COMMENT IN THE PROCEDURE DIVISION
DISPLAY "SPECIFYING COMMENTS IN THE PROGRAM".
STOP RUN.
**************************** Bottom of Data ****************************