What is the difference between a glider and a sailplane? The words "glider" and "sailplane" seem to refer to similar or the same type of aircraft. In particular, the Wikipedia articles "Glider (aircraft)" and "Glider (sailplane)" seem to be describing the same kind of aircraft.

What is difference between a glider and a sailplane, if any?
The sailplane article is focused around sport and recreational planes. The aircraft article describes a wide variety of aircraft, not simply planes, like hang gliding and paragliding.

Which makes sense - one is about aircraft, so it has the aircraft moniker. The other is specifically about planes, which are a subset of aircraft, and thus have the sailplane moniker.

There was an idea of merging them in 2011, but it failed.