Fire

Fire is very important for multiple reasons. Primarily, fire is used to provide light at Night, which prevents the Grue from attacking. Additionally, fire allows food to be cooked on a campfire or fire pit, increasing its Hunger and Health values. Fire also provides warmth in Winter, which counteracts freezing. Despite these benefits however, fire can also be dangerous.

Light
There are several sources of Fire which provide light. Most of these can be found in the Light Sources tab, represented by the Campfire icon. These sources include Campfires, Fire Pits, and Torches. Additionally, anything actually on fire, such as plants or items, will give off light as long as it is burning. Light serves several purposes: mainly it is used to see at night, though it is also needed to prevent the Night Monster from attacking. Additionally, light prevents the large Sanity loss that comes from total darkness (however, it does not prevent the gradual loss caused by Dusk/Night time. If Sanity does drop too low, Night Hands will begin to approach the fire and steal portions of it; eventually they may put it out completely. These hands can be scared off by stepping on them and running them towards the edge of the fire's light.

Cooking
Fire Pits and Campfires can be used to cook foods. Cooking has various positive effects. For most foods, the amount of Hunger they restore is increased, and well as a small Health boost. Eating raw Meats decreases Sanity, while cooked meats do not. Additionally, Monster Meat, eaten raw, will reduce health and Sanity, but these effects are lessened with cooking.

Warmth
In Winter, characters will begin to freeze if they are away from Fire for too long (warm clothing helps prevent this). As long as the character is within a certain radius of a fire they will stay warm. This includes any burning objects like trees. Fires can also warm Heat Stones which can be carried around in winter to slow freezing. Torches (when equipped) will give a small amount of warmth, although it will not prevent freezing in snow.

Dangers
Although beneficial, Fire can also be dangerous. Burning plants or trees, items on fire, or even burning creatures can cause fire damage of 8-12 per second if too close (except for Willow). Such fires are also uncontrolled and can spread to any other nearby flammable object. In this way, huge forest fires can begin, which will destroy vast amounts of resources. Campfires (but not Fire Pits) are also considered uncontrolled fires and will spread to nearby objects if they are built too close. Any flammable item that can be picked up will turn to Ash if set on fire, while burnt trees can be chopped for Charcoal. Torches can be used to purposely set things on fire by clicking the torch on the object. It is also possible to light things in the inventory on fire by dragging a Torch over and pressing RMB.

Fuel
Below is a list of what are arguably the best fuel sources, along with their pros and cons:
 * Turf is extremely abundant and is easily collected with a pitchfork, which has a very high durability. However, it only burns for 90 seconds and is not renewable, abundant as it is.
 * Boards burn for the longest time of 6 minutes and it's renewable, only requiring 4 logs. This means it requires a 15 axe swings on a large tree as well as digging up the stump to make one board.
 * Straw Rolls also burn for the longest time of 6 minutes and are also renewable, requiring 9 cut grass. Collecting from 9 grass tufts takes about as long as getting 4 logs, and might even be a little quicker.
 * Grass Tufts and Saplings are very quick and easy to collect, plus they burn for the longest time like boards, however they are not renewable.

In Rain, fuel burns faster (depending on precipitation rate):
 * Fire Pit up to 200% faster
 * Campfire up to 250% faster
 * Torch up to 150% faster

Bugs

 * Sometimes, when (live) Redbirds burn, they can survive and fly away.

Burnable Objects
Under construction.