Datasheet for the STV8211, supplied as a 113 KB PDF document. The name gives only the part number, so details such as package and function must be read from the document itself. STV-prefixed parts are STMicroelectronics devices commonly found in television and display equipment. Repair technicians consult a sheet like this for the pinout, supply voltage requirements, block diagram and typical application circuit, which makes it easier to measure the correct voltages around the chip and judge whether it or its surrounding components are at fault.
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 @datasheet_technar_org. 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.