What makes a diesel engine different to a regular gas engine, and is one better than the other?

Apart from the very curious, not many people ask why diesel engines, compared to gasoline, run higher compression ratios. The argument is reasonably straightforward and starts with fuel ...

Named after Rudolf Diesel, who invented it in 1893, the diesel engine is often associated with a dirty, smoky exhaust — an admittedly nebulous impression in no small part fueled by the black clouds of ...

Every car engine has quite a few details, ranging from cylinder count to compression ratios. How does changing the compression ratio affect the engine?