Char cord (like char cloth) is used to catch a spark, and begin the combustion sequence - furthered by adding tinder to the lit char cord. The advantage of using cord (as opposed to cloth), is that the ember smoulders both hotter, and more slowly, thereby using the fuel material more efficiently.
Bushcraft Essentials Char Cord / Char Rope 50 cm
Teufelberger (New England) Nylon Accessory Cord – T'NT Work & Rescue
Guide: Best Macrame Cords & Ropes
Rope vs Cord - Rope and Cord
Resource: How to Tie Ropes and Cords for Function or Decoration
Paracord, marine rope, equestrian rope, plastic buckles – Cams Cords
Bobbiny™ Macrame Cord 3-PLY Twisted (06999) – Macrame Cords
Paracord Planet Line Winder Rope Organizer - Spool Tool Prevents
Fms Natural Twisted Cotton Strong Triple-Strand Rope