What do you want to know? As for the speed limit signs, they're all like this: http://www.thermmark.co.uk/wp-content/uploads/2017/02/30mph-speed-roundel-product-0-180x180.png with the speed limit in miles per hour inside. And there's also this sign http://www.centraldt.com/wp-content/uploads/2017/02/nsl.png which basically means 60mph, unless the road is a dual carriageway, with a dividing section between the two directions of traffic - when it means 70pmh. The only thing to watch for here is that if the road has this sign and it changes from single to dual carriageway and back, then the speed limit changes without any signage. The speed limit is always signed when it changes. It's often repeated with smaller signs after that, but not always (and it's seldom repeated in London). The safe rule to go by is that if you don't know the speed limit and there are lamp posts by the side of road, then assume the speed limit's 30. If your're out on a country road, outside a town or a village, and ther are no lamp posts, then the chances are that its http://www.centraldt.com/wp-content/uploads/2017/02/nsl.png What else do you need to know? You'll find that a lot of drivers go faster than the speed limits. In London, they know where all the cameras are and they slow down for them. Be careful.