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hello ppl....can some one tell me PLEASE how do i know the codes for pictograms in html or if there is any soft wich help in this i want make a button for exemple crystals and with pic one crystal i did the button but idk how to put the pic idk the code, pls replay back if there is anyone who can explaidn me how the thing works

ty very very very much u helped me so much thank you :*