Constraints in Houdini define how a piece of geometry behave and how they move in the simulation when external forces are exerted upon them. Glue & Spring Constraints both behave differently in the simulation.

Destruction Simulations are controlled by the way you fracture the geometry being destroyed and how the glue constraints are to be broken on impact. Check out this video, where I covered the basics of setting up a destruction simulation using glue constraints provided by the voronoi fracture and I covered some basic concepts for glue constraints, to understand some fundamentals.