Mistress Beata of Angel I signing death sentences on paper
Paper was a material made from wood or by insects such as bees. Paper was often used as something to write or draw on.
Phlox made a model of a Pyrithian moon hawk out of blue paper. (ENT: "A Night in Sickbay")
A Klingon proclamation on Organia was printed on paper. (TOS: "Errand of Mercy")
The Elected One, Beata of Angel I, signed several documents on paper. (TNG: "Angel One")
Paper was also used on planet Malcor III. Chancellor Avel Durken put a stamp on several Malcorian documents on paper. (TNG: "First Contact")
Paper could be used to wrap gifts. In 2365, Wesley Crusher told him he was supposed to rip it off, but the android replied that by removing it carefully, it could be reused. When Crusher further protested, Data proceeded to tear the otherwise still intact wrapping paper in half. (TNG: "The Measure Of A Man")
Members of Makull's species still used paper, to print flyers, for example. (VOY: "Time and Again")
Jake Sisko wrote Anslem on paper given to him by Onaya. (DS9: "The Muse")
In 2372, Harry Kim played a jazz impromptu on his clarinet from a paper score. (VOY: "The Thaw")
In 2374, Chakotay used paper to remember his time with Kellin on board USS Voyager before he forgot about her due to a virus that wiped out computers' and individuals' memories of anyone who was in contact with a Ramuran. (VOY: "Unforgettable")