Is Idling to Warm Up My Car in Winter Really Necessary?

When cold weather hits, most of us sit in our cars longer, letting them idle to warm up the engine. But is this seasonal habit necessary or is the idea of needing to warm up cars a myth? Recently, several articles have been published on this subject. Some say that newer cars don't need to be warmed up, while others insist that idling is a good idea for both new and old vehicles. Read on to hear opinions from both sides.