People write nu when they mean new, but they want it to look cool and a little different. You meet it most in names of music styles: nu-metal, nu-jazz, nu-disco. It tells you this is a fresh kind of an older style, not the old style itself. It is not a word you drop into a normal sentence. You would not write “I bought a nu bag”; a teacher would just see a spelling mistake. It lives on album covers, posters, and magazine labels. Older listeners may still say “new metal”; fans often write nu-metal as if that were the real name. Though actually, the same spelling is also the name of a Greek letter, and in some Jewish families nu is a little word like “so?” or “well?” — but the nu on those album covers is only a stylish new.