music represents periods of your life. there may be a time where you love this particular music, listen to it often, or even set it as your message ringtone. and coincidently, you message this particular person frequently, at that point of time. however, things changed. and that music is no longer to your liking. and therefore, had a change of ringtone. time past. and that music you used to love, comes to you again. you soon indulged yourself in reminiscence. feeling a little heart aching but having a tinge of happiness at the same time.

smell, represents periods of your life too. often, when you walk past somewhere, you may smell a scent from past. and feel nostalgic all over. you will start racking your brains, trying to remember when was that period of time. nevertheless, you just can't remember. and that, leaves you a small mystery. after time, you soon forgot the scent of the smell and that mystery remains a mystery forever.

words and behaviour too, represents time of your life. you grow up. the choice of words in your language changed. and in turn, behaviour changed. someday, you come across those words you used to use and love. a nostalgia for the past.