The instrument described is a clavichord.
Although not very popular nowadays, it was important between the 15th and the 19th century. In popular music, variations of it can be found in songs by artists such as Stevie Wonder and Bjork, but they mostly used the electric version of the instrument.
An outline is being defined as a 2 dimensional shape which is the answer. The outline also known as the list being arrange to portray the hierarchical relationship and known as a tree structure. It is used in order to portray the main points or a topic in a subject.
