Tchaikovsky's music is deservedly popular, and some of his most instantly recognisable music is from his ballet "The Nutcracker". The story is set at Christmas time, and is full of lots of small gems such as "The Sugar Plum Fairy". The main instrument you can hear in the full orchestral version is a celesta (or celeste), which is a keyboard instrument which sounds like a music box. Because it is a keyboard instrument this part can also be played on the piano, and here we have simplified this part and added music from the other instruments to create a full arrangement for piano solo. The sheet music can be seen below the video. When practising this arrangement it might help to think of the orchestral version and imitate those instruments. For reference here is the Sugar Plum Fairy in its original orchestral score, and on youtube here is an attempt to recreate the orchestral sound live using keyboards.