Abbreviation of "do" + "you". Used while texting. It is faster than writing "do u" where "you" has been abbreviated to just "u" due to both sounding the same.
*Whilsttexting*
Boy !: dyu want to go to the cinema
Boy 2: yh sure
And dying in yo' bed many years from now, would ya be willing ta trade all da days from dis here day ta dat fo' one chance, just one chance, ta come back here as young men an' tell our enemies dat dey may take our lives but dey will never take our freedom ... YUB NUB!