What is a?

what does poser mean? oh and dont tell me look it up in the dictionary im too lazy thats y.i dont now why people call me a poser if my perants dont llike rock music i cant berley find out of my favorite band, but im soo a fan of My CHeMicAL RoMAnE and now that i know all the songs of mcr its alright if they or someone calls me a poser but if poser means a bad ype of way dont say that word to me cuz its rude to others thx and plz answer my qouestion thank u