We read rhythms by observing the shape of the note. Each musical rhythm is portrayed by a differently shaped note. A whole note is the longest fundamental rhythm of most modern music. By fundamental, I mean it is the longest rhythmic value represented purely through notation. Other notational additives, such as dots and ties, can be used to lengthen a circle. We will discuss these additives in more detail in future lessons. The whole note is the shape of a hollow circle. Its value is always equal to the whole base value of the time signature.
A half note is a circle with a line extending from one side. This line is called a stem. This additional physical characteristic is the only thing that distinguishes this rhythm from a whole note. A half note receives half of whatever the base value is set in the time signature.