About 7,450 traditional and 1,450 simplified character shapes (glyphs) are listed in the CCD, divided over more than 1800 series. These series are clustered into 393 character tables (CTs). All characters have been assigned a CT, and so, when creating the CCD we had to decide under which of its components – and therefore, in which CT – characters and headers were to be listed. For example, a character like 章 could have been listed under 立, or under 日, or under 十. Of course, we could have listed the characters under all three components, but that would mean duplication of the same information and is unpractical and a waste of space.
In order to solve this problem an analysis was made of all non-radical components necessary to identify characters. It appeared that a minimum set of 393 components was required, which was turned into a table called the Main Components Table or MCT. As a result, each character in the CCD has at least one component that is a member of this MCT. Then we went on to list all characters according to the order of the MCT. But then there was a problem: how to arrange 8,900 different character shapes under these 393 headings?
Most characters consist of more than one component, some have radicals, some have not. Obviously, we had to establish an order among the components characters are made up of. In languages that have words written with the help of an alphabet this is easy. You start at the left, and assign that letter the status of most important, the second becomes the next most important, etcetera. But Chinese characters are just a bundle of components without left-right, or right-left ordering. So we had to create an alternative way of ordering components, relying completely on the MCT.
First we decided to discard frequently used radicals that stand apart from the main body of the character, as we wanted to group characters with the same phonetic but different radicals into series. Then we determined the place of each of the remaining components in the MCT, and next we assigned each component a priority according to their position in the MCT. The highest priority was assigned to the component that is nearest the beginning of the MCT, and we decided that that component would be called the first component of that character, while the component that is next in the order of the MCT would be called the second component, etcetera.
Therefore, we first formed CTs by gathering characters under the first of its non-radical components that can be found in this MCT, and grouping them further into series based on the second MCT-component they have in common, and finally ordering them according to the MCT-order of the remaining components, including radicals. Using this method it was possible to assign each character a unique place.
If we want to find a character in the CCD we obviously have to use the same method, as explained in detail in How to use the CCD.