Short answers, pulled from the story.
Artemis was born first before her twin brother Apollo on the floating island of Delos. The island of Delos was once drifting freely across the Aegean before it was anchored to the sea floor by the weight of the newborn twins.
Artemis's symbols included a bow and arrow, a quiver, and hunting knives. The deer and the cypress were sacred to her, and she was often depicted as a huntress of the woods surrounded by her chaste band of nymphs.
Artemis turned the hunter Actaeon into a deer and had him devoured by his own hunting dogs because he saw her bathing naked in her sacred spring. This act of hubris resulted in his death as a punishment for transgressing upon her sacred space.
Artemis halted the winds blowing the Greek ships during the Trojan War after King Agamemnon shot and killed her sacred deer. She demanded the sacrifice of Iphigenia, Agamemnon's young daughter, as compensation for her slain deer before taking her away and leaving a deer in her place.
The etymology of the name Artemis remains uncertain though various origins have been proposed including a Pre-Greek origin, a Phrygian root, or a Persian origin meaning great, excellent, or holy. The name may be related to Greek arktos bear, supported by the bear cult the goddess had in Attica and the Neolithic remains at the Arkoudiotissa Cave.