Feather quills are writing instruments made from the feathers of birds, typically geese or swans. The hollow shaft of the feather is shaped into a pointed nib, allowing for smooth ink application on paper. Historically, quills were the primary tool for writing before the invention of modern pens, and they were often used by famous writers like William Shakespeare. To use a feather quill, one must dip the nib into ink, which can be made from various natural materials. The flexibility of the quill allows for different line thicknesses, making it a versatile tool for calligraphy and artistic writing.