Classify the following types of polyethylene based on their branching structure: High-Density Polyethylene (HDPE), Low-Density Polyethylene (LDPE), Linear Low-Density Polyethylene (LLDPE), and Ultra-High Molecular Weight Polyethylene (UHMWPE). Which category best describes HDPE?

High‑density polyethylene (HDPE) is a nearly linear polymer with very few branches, giving it a high density and good strength. Low‑density polyethylene (LDPE) has many long, irregular branches that make it less dense and more flexible. Linear low‑density polyethylene (LLDPE) contains short, regular side branches, placing it between HDPE and LDPE in density. Ultra‑high molecular weight polyethylene (UHMWPE) is also linear and lightly branched, but its molecules are extremely long, giving it exceptional toughness. Thus, HDPE belongs to the linear, low‑branching, high‑density category.