RAR package labeled Vostro 1088 for a Dell notebook, about 676 KB in size. The name states only the model designation, so the actual contents, likely a schematic or other repair data, should be confirmed after opening it with an archive program. Service files of this kind help trace power rails, check the charging circuit and identify components when a board will not power on. Check the board number printed on the PCB against the document, since Dell models are built by different ODMs and layouts can vary.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @IT_SERVICE_WORLD. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.