The Sharp X1 is a computer made by Sharp. There were a few upgraded models such as the X1 Turbo that had support for higher resolution graphics.
Mainly the library consists of arcade ports, strategy games, action RPGs (such as the Ys series) and adventure games with a few action/arcade styled games. It is also home to a few Nintendo based games as well from NES ports to original games based off existing games such as Punch Ball Mario Bros.
Some Sharp X1 games can be ripped via tile viewers such as YY-CHR however many can't so currently the only way of getting the sprites is via capturing due to lack of tools for the computer.
The common source code project supports all the models of the computer and has the ability to screenshot.