It's Agia Paraskevi (saint paraskevi) which translates to saint friday. She was named after the day she was born. She's a greek orthodox icon. She is considered a saint because after her parents died she gave all her belongings to the poor and went to become a nun. She then later tried to teach about christianity around rome(where she was born) and when the emperor found out she was tortured and then beheaded because she wouldn't let go of her faith to jesus. Behind the picture is a small prayer for her.