Short answers, pulled from the story.
Marsyas was a young satyr musician who found an aulos double reed instrument near the river Meander in Phrygia. He became an expert player of the double-piped instrument after ignoring Athena's curse that anyone picking up the pipes would meet an awful death.
Marsyas played his flute and put everyone into a frenzy while Apollo played his lyre so beautifully that listeners stood still with tears in their eyes. The Nysean nymphs supported Apollo's claim leading to his victory and Marsyas being flayed alive in a cave near Celaenae for his hubris.
The dithyrambic poet Melanippides of Melos embellished this story around 450 BC claiming the goddess threw away the flute because blowing into it made her look silly. Despite doubts from fifth-century BC poet Telestes the story became accepted as canonical.
Mythographers situate Marsyas episodes in Celaenae or Kelainai in Phrygia which marks the main source of the Meander river in modern Turkey. Herodotus linked the river to the figure of Marsyas in Histories 7.26 and Xenophon mentioned the connection in Anabasis 1.2.8.
Among Romans Marsyas was cast as the inventor of augury and proponent of free speech serving as an indicium libertatis symbol of liberty. The earliest known representation stood for at least 300 years in the Roman Forum near the comitium where invective verse was posted on his statue.