How are traffic jams created and is there any way to fix them besides mass transportation?

Traffic Jams have a simple cause...too many cars, not enough road.

Beyond that however, things get surprisingly complicated.

Laws that prohibit actions that incite traffic jams are the best place to start...for example, no "blocking the box" in dense urban areas.

Expansion of highways are a good solution to congestion, but do not always have a positive effect. In some urban areas (LA for instance), recent studies have show that highway expansion actually INCREASES congestion by raising the desirability of the highways BEYOND the increase of its load capacity. In other words, people who think the highway will now be a quicker route to their destination will take IT instead of the alternate routes they would normally take...defeating the purpose of expansion.

Traffic incidents (accidents..etc.) are the largest cause of congestion in the US. Systems that efficiently track incidents along the highway network and communicate that information to drivers, and response crews can decrease congestion by up to 20% alone.

In areas of construction, the merge method employed is usually the biggest controllable factor in minimizing congestion with the "late" or "last minute" merge being the most effective in theory. When it is employed in such a way that drivers are informed of a merge ahead of time, it becomes one of the least effective, as drivers merge too soon, causing traffic ghosts, and failing to utilize the entire load capacity of the blocked lane.

There are entire sets of theories behind traffic congestion relief.

I recommend the book "Traffic: Why we drive the way we do and what it says about us". It wonderfully written and researched, and is very enlightening if you are interested in urban/civil engineering.

To many Vehicles on the road maybe? Bigger and better designed Highways maybe?

Traffic jams occour because everyone works at the same time
a rotating work schedule would help

Besides sheer volume. The biggest reason are THE DRIVERS!!!!!! Mass trans wont do it. It needs to be a better screening process to liscense people. So basiclly its too many drivers and not enough people that know how to drive.