What exactly is a veranda, and how does it differ from a porch or pergola?

A veranda is a roofed, open‑air space attached to a house, typically wrapping around one or more sides. It always has a solid roof, may include railings, and is designed as a true outdoor living area, unlike a porch, which might just cover an entryway. Pergolas, by contrast, use an open‑beam or lattice roof, not a solid one.