Sara Pyszka, 19, is an accomplished singer. But what's most incredible about her performances is that she cannot speak.
Pyszka was born with cerebral palsy and has never been able to walk, talk, or use her hands.
But when her school bought her a computer with an electronic voice, she was no longer silent.
"To tell you the truth I don't think of myself as any different," she said. "I was never able to really talk. So I did not know what it was like to talk."
A touchpad on Pyszka's wheelchair, which sits next to her head, is connected to her computer. Using her head, Pyszka clicks on words and phrases. The technology allowed the teenager who loves to compose music to actually perform it.
"There was an exciting young lady in there," said Pyszka's mother, Cindy. "She had a lot to say."
Pyszka attended a music camp for the disabled and began studying under Lucas Richman, the former conductor of the Pittsburgh Symphony Orchestra. He asked her to sing one of her songs during a performance.
"I'm just amazed at her ability and her sense of self," Richman said, "and her ability to perform in front of thousands of people."
Pyszka's list of performances quickly grew: a high school basketball game, a Cleveland baseball game, and the Republican National Convention. When she goes off to study at Wright State University in Dayton, Ohio, in the fall, she will carry with her the pride from her performances.
Last week, in front of the Pittsburgh Pirates and thousands in her hometown, Pyszka sang the "Star Spangled Banner" to open the ball game.
"It has been one of my dreams for about three years now and I finally did it," she said.
ABC News' David Muir filed this report for "World News Tonight."