The vintage fountain pen is a type of writing instrument that contains a reservoir of water-based ink that is fed to a nib through a "feed" via a combination of gravity and surface tension.

The nib is usually made of stainless steel or gold. In some pens, the point is made of platinum, due to the need for it to be smooth and very hard. Pens with steel points eventually wear out due to abrasion by the paper.

The nib usually has one slot cut down its center, to convey the ink down the nib. The whole entire nib narrows to a point where the ink is transferred to the paper. Broad calligraphy pens may have several slots in the nib to increase ink flow and help distribute it evenly across the broad point.

Although the most common nibs end in a point of various sizes (small, medium, broad), other nib shapes are available. Examples of this are oblique, reverse oblique, and italic.

Fountain pens are widely regarded to be the best tools for writing or drawing with ink on paper. However, they are much more expensive, harder to maintain, and more fragile than a ballpoint pen. In addition, they cannot be used with the various oil and particle-based inks (such as India ink) prized by artists, as can a dip pen, reed, or quill.

Vintage fountain pens are often works of art. Ornate pens made of precious metals and jewels are made, appealing to the same people who like diamond encrusted gold Rolex watches. However, good quality steel pens are available for only a few dollars. Even some "disposable" fountain pens are available.

Avid communities of pen enthusiasts collect and use antique as well as modern pens and also collect and exchange information about old and modern inks, inkbottles, and inkwells. Collectors often tend to prize being able to actually use the antiques, instead of merely placing them under glass for show.

Companies that manufacture fountain pens include Parker, Pelikan, Waterman, and Sheaffer. Companies who manufacture high quality ink include Private Reserve and the French company Herbin. Pilot is one of only a few companies that make disposable fountain pens.