The traditional method of identifying a Chinese character from its appearance is to find within it the number of its base radical (one of 240 shape groups), count the number of extra strokes apart from the radical, then look the character up in tables organized by the radical and the number of extra strokes.
Over the years, radicals have undergone many changes of appearance, in particular simplified forms have been introduced, and a complex character may appear to contain several radicals to choose from, or no radicals at all. A scholar can explain how or why the modern form or forms of a character has been arrived at, but this is no help to someone learning characters for the first time.
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