Books were very expensive in the Middle Ages. Most Medieval Manuscripts were works of monks. Making a book took many hours by a team of craftsmen, scribes, illuminators and bookbinders. In some monasteries the scribes worked at separate desks placed in a large room. In other monasteries each monk worked in his own cell.
Before writing the scribe ruled the page marking off the margins and drawing guidelines. These lines were made with a metal stylus or a pen without ink. This was usually the job of the apprentice.
The pens were made from a reed or a quill of a large bird. These pens were cut with a wide end like a chisel. The full width of the pen was used when a downward stroke was made. This made a wide line. Only the fine edge of the quill was used when it was moved crosswise. This made a thin hairline stroke. This made the letters shaded as the writer traced their curves and angles.
The ink was wither lampblack or made from iron filings and oak bark boiled in vinegar.