Compressed archive for the IBM ThinkPad T23, about 1.5 MB in RAR format. The name gives only the model, with no board number, revision or indication of contents, so open it with WinRAR or 7-Zip first. Material for this kind of notebook usually serves for following power rails from the DC jack, checking regulators, identifying components and finding test points on the system board. Before relying on any document inside, verify that the board identification on your unit matches the one shown in the files.
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 @alischematics. 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.