Musician is cartridge number 31 in the official Magnavox/Philips line of games for the Philips Videopac. It came in a cardboard box roughly double the size of a standard Videopac game box, containing a keyboard overlay in the style of a piano keyboard; the cartridge, in a standard Videopac box with a single sheet where the manual would usually be; and a landscape format manual, over double the size of a standard game manual.
The purpose of the set is to turn the user's Videopac into a musical keyboard. It supports recording and editing sequences of up to 81 notes, although there is no way to save apart from writing a composition down on music manuscript. In the manual there are the following pieces of sheet music:
"Badinerie" (Bach)
"Brother Jacob"
"The Entertainer"
"Eurovision Tune"
"Happy Birthday to You"
"Liebestraum" (Liszt)
"Lightly Row"
"Merrily We Roll Along"
"Michael Row the Boat Ashore"
"Mosocow Night"
"Old McDonald Had a Farm"
"This Old Man"
"Three Young Drummers"
"Twinkle Twinkle Little Star"
Source: Wikipedia, "Musician (video game)", available under the CC-BY-SA License.