Goddess's Harp

The Goddess's Harp is an item from The Legend of Zelda: Skyward Sword. It is a relatively large golden Lyre. The harp's primary purpose is the playing several songs vital to Link's progress in his quest. It may also be used to cause Gossip Stones or Goddess Walls to appear in certain areas with multiple Blessed Butterflies flying around them.

Equipped to the up-button on the D-Pad, the Goddess's Harp is played by directing the Wii Remote to the left or right, respectively corresponding to the lower and higher notes. When a song has to be played, Link is given a visual cue that indicates when to strum the harp. These cues vary depending on the situation; usually, Link must follow a circular symbol that expands and retracts.

Story
At the game's beginning before the commencement of the Wing Ceremony, Zelda is given the Goddess's Harp to play. When she is attacked by Ghirahim's evil tornado and sent to The Surface, she keeps the harp on her person, and brings it along with her on her journey across The Surface. After praying at the shrine in the Temple of Time, Zelda and Impa meet up with Link. However, they are attacked by Ghirahim, and Zelda is forced to escape together with Impa by way of the nearby Gate of Time; before leaving, she manages to toss Link the Goddess's Harp.

With the harp in hand, Link returns to the Sealed Temple, where the Old Woman there teaches him the "Ballad of the Goddess". Once he has learned a song, when playing a song he must act as accompanist to Fi, who performs the vocal part. Later, he travels to the Isle of Songs on several occasions to learn songs to unlock the Silent Realm trials of the three regions of The Surface. Lastly, Link must learn the different parts of the "Song of the Hero" from Levias and the Three Dragons in order to unlock Skyloft's trial.

Theory
The Goddess's Harp resembles the Harp used by Sheik in Ocarina of Time. This could be meant to show that the Goddess's Harp will become an heirloom of the Hyrulean Royal Family. The method Zelda uses to transport herself to the different temples is unknown, leaving the possibility that she is using the Goddess's Harp to warp to these places, in the same way that Sheik teaches Link melodies that allow him to warp to different temples.