Structures and data are declared like this:
TYPES: BEGIN OF struct,
number_1 TYPE i,
number_2 TYPE p DECIMALS 2,
END OF struct.
DATA: wa_struct TYPE struct,
number LIKE wa_struct-number_2,
date LIKE sy-datum,
time TYPE t,
text TYPE
string,
company TYPE s_carr_id.
The data is accessed in a program by referring to it directly. For example if I wanted the value stored in the date field, I would reference it by writing wa_struct-date. The data structures are comparable to classes without any methods I guess.