There are two main types of drawing ink: pigment ink and dye based ink. Pigment ink is archival, waterproof and fade proof. Dye based ink, on the other hand, is water-soluble. There will however be slight exceptions but these are the main differences.
Drawing pens come in many forms: quill, reed, dip, fountain, ball point, gel, technical, felt tip, brush and so the list goes on. For convenience, I recommend using fountain pens or technical pens. Uni pens or Sakura Pigma Micron pens are good examples of the metal tipped technical variety. Although fountain and technical pens are convenient to use, there is one main difference. Fountain pens have a flexible nib that can produce lines of varying width depending on the amount of pressure exerted when drawing.
Modern fountain pens will have disposable ink cartridges. Most of these cartridges contain dye based (water-soluble) ink. If you wish to use pigment (waterproof) ink in your fountain pen, you can purchase a 'converter' that replaces the disposable cartridge. The converter can be filled directly from a bottle of pigment ink specially designed for fountain pens. Platinum carbon ink is one such make. I use a Lamy Safari fountain pen with a converter, an extra fine nib and black pigment ink. If you prefer water-soluble ink and the flexibility of a fountain pen nib, then the Rotring drawing pen would be a good choice