Type Group

• A type group/pool is sort of like an INCLUDE program which you use to put all of  your TYPES statements into, mostly it is used for reuse, so you define your TYPES there, and they can be included in any program, or class, and be used within.
• Ex : SLIS , ABAP
• SLIS.

• ABAP

• To use them in program we use key word ‘TYPE-POOLS’.
• It allows us to define non-predefined types. 
• Combination of all such non-predefined types is knows as type-pool or type-group. 
• In simple terms, if we want to use some custom types in various programs then we need not define them separately, we can simply create a type group in ABAP dictionary and use that in our programs.

Steps

• Go to transaction code : SE11.

• Click on Type-Group radio button.

• Enter the type-group name start's with Y or Z<Type-group name> and click on create.

• Enter short description and required types , constants.

Note : Variable's name must start with <Type group name>_.

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