A campfire
A campfire was a fire lit in the outdoors while camping. This fire would be used to cook food or keep warm.
Henry Starling was sitting next to his campfire in the High Sierras in 1967 when the timeship Aeon crash landed next to him. (VOY: "Future's End")
Some inhabitants of Bozeman, Montana used campfires to cook their meals in 2063. (Star Trek: First Contact)
A sort of campfire was lit in a street of a city on the Akaali homeworld with food cooked over it when the landing party of Enterprise NX-01 visited the place. (ENT: "Civilization")
Tucker told Captain Archer after dicussing the behavior of the Takret that by this time they had a camp built at the rim of the canyon and also lit a fire regarding their previous exploration mission on the surface of an uninhabited planet. (ENT: "The Catwalk")
In 2287, James Kirk, Leonard McCoy, and Spock lit a campfire in Yosemite National Park. They used it to cook Southern baked beans, toast marshmallows, and to sleep near. They also sang "Row, Row, Row Your Boat" around the fire. After their mission to Nimbus III and the Great Barrier, they did so again. (Star Trek V: The Final Frontier)
The musket-wielding aliens created by Q in 2364 had a campfire near their tents. (TNG: "Hide And Q")
Ramsey, one of the survivors from the Odin, had a campfire near the cave he was living in on the planet Angel I. (TNG: "Angel One")
Data once described campfires as "thermal radiation and carbon dioxide emissions, indicative of combustion". He did this in 2366 while in search of the Acamarian Gatherers on Gamma Hromi II, who maintained several campfires. (TNG: "The Vengeance Factor")
The fully-Klingon B'Elanna Torres made a campfire for herself and the Human Torres after she rescued her from the Vidiian barracks. (VOY: "Faces")