According to cultural sociologist Monique Charles, grime is typically characterised by four beats to a bar, in 8 or 16 bar cycles. It is one of the reasons why grime was unofficially called 8 bar or 16 bar in its formative years. 8-bar is a subgenre or style of grime, first seen in Youngstar's "Pulse X" instrumental. 8-bar instrumentals switch beats every eight bars, meaning that each 8 bars the MC would be rapping over a different rhythm. This was in contrast to "nu shape", another style of grime which encouraged 16–32 bar patterns.
