RAR archive of 1.50 MB labelled Toshiba M18, with no further detail in the name about laptop model, board maker, revision or document type. M18 may be a model or board designation, but that cannot be confirmed from the name, so open the archive and find the board number inside. Compare it with the PCB marking before using it. Repair documents like these let a technician trace rails, follow the power-on sequence, locate test points and identify components when diagnosing shorts or power failures.
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.