So, most of my current research is on pulsars and pulsar accessories. Part of me wants to go "ok everyone knows what a pulsar is so let's go straight to talking about the advanced stuff" and then i remember that one xkcd comic about experts so:
Pulsars are rapidly rotating neutron stars with bright “beams” of radiation that sweep across the sky. When these beams happen to cross over Earth, we detect a “pulse”, much like a lighthouse appears to pulse as it sweeps across a given vantage point.