Table Type is used to refer multi line data types. It has line type field to hold data type of one template line. Besides, Table Types have performance related attributes to better access the referenced data.Below picture shows these access types for Table Types.
Using one of these access types according to your needs you can increase your internal tables access performance. In object oriented arhitecture Table Types plays an important role as object oriented ABAP does not allow ‘Tables’ keyword which is available in procedural programming. In ABAP without declaring dictionary object you can create Table Types with TYPE TABLE OF or LIKE TABLE OF keywords.
Below you can see how to create a sample Table Type with a structure line type.