A Heegaard splitting divides a closed three-manifold into two handlebodies with common boundary. For a three-manifold with boundary, one uses compression bodies, which can retain negative boundary components.
Heegaard splitting is a concept from the field of topology, specifically in the study of 3-manifolds. It provides a way to understand the structure of a 3-manifold by decomposing it into simpler pieces. The key idea revolves around the partitioning of a 3-manifold into two "handlebodies.
New to topics? Read the docs here!