Shakyamuni Buddha symbolises the enlightened quality of the mind, a state all sentient beings can attain. He also symbolises all human characteristics in their pure form. By training the mind, human defilements can be abandoned and enlightened qualities of mind can be developed. Everyone can attain such state – that is what Buddha Shakyamuni has shown and transmitted. Therefore his image is very popular and is used to remember oneself about those enlightened qualities and to help develop them.