Parapin makes it easy to write C code under Linux that controls individual pins on a PC parallel port. This kind of control is very useful for
electronics projects that use the PC's parallel port as a generic digital I/O interface. Parapin goes to great lengths to insulate the programmer
from the somewhat complex parallel port programming interface provided by the PC hardware, making it easy to use the parallel port for digital
I/O. By the same token, this abstraction also makes Parapin less useful in applications that need to actually use the parallel port as a parallel
port (e.g., for talking to a printer).