If something is waterproof it means it is impervious to water, whereas water-resistant means its able to resist the penetration of water to some degree but not entirely. There's also such thing as water-repellent, which tends to mean the item has been treated with a water-resistant coating.

Original Gore-Tex products offer guaranteed waterproof, windproof, and breathable protection, so yes, in short, it is.

You can pick up a minimalist Rains' coat, look sophisticated and stay dry in it, or you could head over to The North Face for an equal parts sensible and sartorial silhouette instead. On the high-street, look to ASOS for water-repellent parkas and trench coats, and if you're worried about the logistics of carrying one around when it's not drizzling, most waterproof jackets and coats feature a packaway design, so you can store them neatly in your bag.