From Academic Kids
The glockenspiel (German, "play of bells", also known as orchestra bells and, in its portable form, lyra) is a musical instrument in the percussion family. It is similar to the xylophone, in that it has tuned bars laid out in a fashion resembling a piano keyboard. The xylophone's bars are wooden, while the glockenspiel's are metal.
The glockenspiel, moreover, is much smaller and higher in pitch. When used in a marching or military band, the bars are sometimes mounted in a portable case and held vertically. In orchestral use, the bars are mounted horizontally. A pair of hard mallets are generally used to strike the bars, although if laid out horizontally, a keyboard may be attached to the instrument to allow chords to be more easily played. One piece where such an instrument is used is Mozart's The Magic Flute (although that part is usually played by a celesta nowadays). A more modern day piece to use the glockenspiel is the 1977 Brothers Johnson remake of Shuggie Otis' classic Strawberry Letter 23. An even more modern use of the Glockenspiel is Radiohead's song No Surprises from their 1997 album OK Computer (played by Jonny Greenwood).
The glockenspiel's range is limited to the upper register, and usually covers about two and a half to three octaves. In sheet music, the notes to be played by the glockenspiel are written two octaves lower than they will sound when played. When struck, the bars give a very pure, bell-like sound.
Other instruments which work on the same struck-bar principle as the glockenspiel include the marimba and the vibraphone. There are also many glockenpiel-like instruments in Indonesian gamelan ensembles.
In Germany, a Carillon is also called a glockenspiel.