COBOL Reserved Words

In this topic, we described about the Reserved Words with detailed example.

A reserved word is a character-string with a predefined meaning in a COBOL source unit.

Below are the types of reserved words -

Reserved Word	Description
Keywords	Keywords are reserved words that are required within each program coding. Such keywords appear in uppercase on each sentence, entry, or statement.
Optional words	Optional words are reserved words that do not affect the execution of the program. They can be included in a sentence, entry, or statement format to improve readability.
Figurative constants	Figurative constants are reserved words and refer to specific constant values.
Special character words	Special character words are used for special purpose. There are five types of special character words when represented as single-byte characters - Arithmetic operators: + - / * ** Relational operators: < > = <= >= Floating comment indicators: *> Pseudo-text delimiters in COPY and REPLACE statements: == Compiler directive indicators: >>
Special registers	Special registers names storage areas generated by the compiler. Their primary use is to store information produced by specific COBOL features. Each storage area has a fixed name and should not be required to define within the program.

Below list shows the examples for each type of Reserved Words -

Type

Some Examples

Keywords

ACCEPT
ACCESS
ADD
AFTER
ALL
ALPHABET
ALPHABETIC
ALPHANUMERIC
ASCENDING
ASSIGN
AUTHOR 
...

Optional words

SKIP1
SKIP2
SKIP3
ROUNDED
...

Figurative Constants

ZERO, ZEROS, ZEROES
SPACE, SPACES
HIGH-VALUE, HIGH-VALUES
LOW-VALUE, LOW-VALUES
QUOTE, QUOTES
NULL, NULLS
...

Special character words

Type	Some Examples
Arithmetic operators	+ - / * **
Relational operators	< > = <= >=
Floating comment indicators	*>
Pseudo-text delimiters in COPY and REPLACE statements	==
Compiler directive indicators	>>

Special registers

ADDRESS OF
DEBUG-ITEM
FORMAT OF
LENGTH OF
LINAGE-COUNTER
RETURN-CODE
SORT-RETURN
WHEN-COMPILED
...