PDF for the BQ24721C, a Texas Instruments laptop charge controller, filed at 1.91 MB. The document likely provides the pinout, typical application circuit and electrical limits for the C variant. It is handy for identifying the components around the charger on a notebook motherboard, checking adapter and battery sense voltages, and judging gate drive to the input and charge MOSFETs when a machine fails to charge or will not start on AC. Make sure the suffix printed on the chip matches, since variants can behave differently.
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 @laptopbios21. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.