total SAP-ABAP can be divided into
Report is nothing but displaying the data in most structured formatt.
This is similar like any general report like G/L Accounts report erc.
Reports are two types.
2 Interactive reports
Classical report is just an output for an input specified.
Interactive report is report where a output is displayed and on events on the output another report is generated .
This are list reports where you write statements
There are reports based on ABAP LIST VIEWER ( ALV) where you use standard function module REUSE_ALV_LIST_DISPLAY OR REUSE_ALV_GRID_DISPLAY this reporst also have diff options and functionality like download to excel ,sorting ,subtotal ,totals ,changing the layout .
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