Displacement is the simplest, most powerful trick in modern groove playing. You take an established pattern — a backbeat, a kick figure, a hi-hat shape — and shift it by an 8th or a 16th. Everything else stays the same. The result sounds wildly different even though only one parameter has changed.
The most useful kind of displacement is backbeat displacement: instead of the snare on beats 2 and 4, the snare lands on the &-of-1 and &-of-3 (an 8th-note displacement) or on the e-of-1 and e-of-3 (a 16th-note displacement). The bar still feels like it has a backbeat — the groove still has weight on the second and fourth quarter — but the snare is no longer where you expect it.
Chris "Daddy" Dave, Mark Guiliana, and the entire generation of drummers descended from drum-and-bass production live in this language. Used sparingly, it adds spice. Used heavily, it's an entire style.
Why It's Hard
Your body wants the snare on 2 and 4 because every other groove you've ever played has reinforced that habit. Displacement requires you to defeat the muscle memory at the same time as you maintain the rest of the groove. Practise slowly, and don't move on until the displaced bar feels as steady as the standard one.