Sign

From Zelda Wiki.org

Signs are found all over in the Zelda series, but mostly in the 3D games. They often provide helpful information or hints on what to do next. Link can often chop them down with his sword. In Ocarina of Time, if he plays Zelda's Lullaby in front of a broken sign, it will piece itself back together; signs can also be repaired by playing the Song of Healing in Majora's Mask and by playing the Wind God's Aria in The Wind Waker. In Oracle of Seasons a Subrosian will give you the Sign Ring for breaking 100 signs. In Twilight Princess, it is possible to pick up pieces of a destroyed sign.