Styles of ascent in sport climbing

On sight flash - The ultimate style of ascent. You turned up and led the route without any prior knowledge of the climb and didn't fall off once. Chalked holds and having the quickdraws in place can dramatically improve your chances of success, though some people would deem this not a true on-sight.

Flash - This is a grey area. A flashed ascent assumes some prior knowledge of the route without having actually climbed any of the moves. 'Prior knowledge' can vary from overhearing a conversation about the crux, to abseiling down the route to look at the holds!

Beta flash - This is really the same as a flash. It's a term invented for leading a route knowing how to do all the moves, by either being told before you set off or with someone shouting them out as you climb.

Redpoint - To climb on lead from bottom to top, having already practised the route, without weighting any of the protection. Unlike on-sighting and flashing, there is no confusion with this style of ascent. A redpoint ascent encompasses any amount of pre-practice from five minutes to five years (or more!). Many people have the rope pre-clipped through the first bolt to inspire confidence and save energy. This is often considered only valid if you climb up to the first bolt, clip in the rope and climb back to the ground.

Top-rope - Climbing tied into a rope from above. It's not common in sport climbing unless the bolts are far apart (and you don't want to get scared). If you are working a route and manage to top-rope it without falling you get no brownie points - you really should have been leading!