Part 2SC5075 gives this 220 KB PDF its name; the catalogue lists it as a schematic, but under Japanese JIS naming the 2SC code means an NPN bipolar transistor, so a datasheet is the likely content. Maker, package and ratings are not part of the name. When a transistor in a power or signal stage fails, such a sheet lets you verify pinout, maximum collector voltage and current and gain before fitting a replacement. Check the original component marking matches first.
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 @cyberlanelectonik. 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.