Short answers, pulled from the story.
Scholars suggest the name Artemis has a pre-Greek source indicated by the interchange between e and i. The Lydian variant Artimus appears in historical records from the Hellenistic period. Some researchers propose a connection to the Greek word arktos meaning bear.
Most sources agree that Artemis was born on the island of Delos because Hera forbade Leto from giving birth on any solid land. Some traditions claim the island where they were born was Ortygia rather than Delos. The Homeric Hymn 3 to Apollo focuses solely on Apollo's birth while sidelining Artemis entirely.
Artemis transformed Actaeon into a stag after he stumbled upon the goddess bathing naked in a sacred grotto. His own hunting dogs did not recognize him and tore him apart in the woods. Ovid describes how fifty hounds devoured their master who could no longer speak or run.
Young Athenian girls between five and ten years old served Artemis at the sanctuary of Brauron to appease an angry goddess following a plague. A myth explains this custom: a bear visited Brauron regularly until a girl teased it to its death. Girls dressed in saffron robes played at being bears during the festival Elaphebolia celebrated on the sixth day of the month.
Artemis halted the winds blowing Greek ships at Aulis stranding the fleet before departure for Troy because King Agamemnon had shot and killed her sacred deer. The seer Calchas advised that only the sacrifice of Agamemnon's daughter Iphigenia would appease the goddess. Most versions state Artemis snatched Iphigenia from the altar substituting a deer in her place.