Before going any further, let me introduce, as a practical tool, a keyboard, that will help us immensely as we go along deeper into the fundamentals of Carnatic music. Purists may frown at this, but as long as we realize the limitations of the keyboard and why the purists frown, we are committing no sin. At first glance, a keyboard is simply an assortment of black and white keys of two different lengths, usually the black keys being the short ones. A closer examination shows a pattern of keys repeating a few times to produce the full keyboard. The repeating pattern is shown in the following figure.
Many keyboards indicate the location of the 'C' key as shown in the figure.
The C key is so called due to the notation used in western music for the notes. The combined sound has an oneness. They do not merge as in the case of the two C keys. Total disharmony is difficult to demonstrate using a keyboard due to the discrete nature of the notes that can be played. Seven white keys and five black keys in between.