When the flint is struck by the steel, it creates sparks which can be directed at the tinder, and cause it to light, thus starting your fire.
Strike the flint with a knife over some tinder
Flint is a rock that you rub to make fire.
fire.
you craft it with stee ingots to make a flint and steel which makes fire.
flint and stone
Flint
Flint and Steel can be rubbed together to make fire.
You can use the knife to create sparks from flint to start a fire.
Creating sparks with flint rocks
Flint, i think
With gravel, get flint from it by hitting it. If it doesn't work first and gravel appears, try again until you get flint. Then, from iron ore, smelt it into an Ingot and craft it with flint and there you will have flint and steel. So right-click the square to set fire, left-click to put out the fire. (NOTE: fire can spread rapidly) With a fire charge you can also do this, but flint and steel have more Effects
Though his face was set like flint, his steely eyes gave a spark of recognition when he saw me. The flying piece of flint gouged my arm. I can usually get a fire started using only a flint and steel.
early man didn't find fire but make it. they made it with flint and steel.