for Cubes up to 5x5x5. SiGN
is more general. I can live with both, but I find it important that somebody using a certain notation states which it is. E.g. the turn "u" is something different performed on a 4x4x4. u in WCA is the inner
layer under face U turned clockwise as U would turn, in SiGN u means both
layers U and the next under it are turned clockwise.