Sunlight, obviously. Fire: candles, lamps, torches, etc.
They would put rocks in a fire and take them out when they got REALLY hot.
They Used a Convex Lens
before toasters people used to toast bread or bagels over a fire . they didnt have electricity in the olden days. you should know this gosh.
By striking FLINT against STEEL over TINDER. Join the Boy Scouts of America and learn how to do it. It could save your life.
well it really is a heated debate. no dumb pun intended. was it man with 2 sticks or not? in my opinion it was lightening strike and the cavemen found the fire and realized what it was and how to use it.
because they are suppose to be mad eof wood so that the light up like in the olden days using woo sticks to make fire
they boiled the water over fire and then trapped the steam and transfered the new clean water to another pot to make in drinkable
By writing letters
Heat Cooking Protection Light Fun
using fire
made by using stones in olden times