Blender processes meshes as polygons and edges under the hood, but there are several ways to visually smooth surfaces—accessible via the contextual (right-click) menu:

• Shade Flat: Blender’s default shading. Displays each face clearly, highlighting the faceted, polygonal nature of the mesh.

• Shade Smooth: Blender smooths shading by interpolating vertex normals. To prevent unwanted smoothing on certain edges, use Mark Sharp on those edges.

• Auto Smooth: Automatically sharpens edges based on an angle threshold. Enabled in the Object Data Properties > Normals panel. Still compatible with Mark Sharp for manual control beyond the threshold.

• Subdivided Mesh: Avoid this method. Over-subdividing the mesh to fake smoothness increases polygon count dramatically and can crash Blender on large models. Use shading techniques instead.