When the amount of data to be displayed by a grid (or free style grid) is not manageable, the user needs to view a subset of sorted data in the screen, and have some paging controls to go to the next and previous pages.
In GeneXus Web Applications, paging can be automatically generated. See Automatic paging in Grid control.
Otherwise, if you want to program the paging controls, it can be done using the NextPage, PreviousPage, LastPage and FirstPage method methods. Follow the Grid paging on the Web guide for more information on this topic.
In GeneXus Web and SD apps, paging can follow the Infinite scrolling pattern.