See how morphology drives properties in polymers and composites. Spherulites, lamellae, crazing, and shear bands are mapped alongside filler dispersion and fiber–matrix interfaces. We connect thermal history and processing—cooling rate, draw ratio, cure—to impact strength, fatigue, and barrier behavior. Fluorescence and polarized light clarify crystallinity and orientation; SEM captures fracture surfaces and pull-out. Practical context links images to packaging, medical, and structural applications.