Traffic in Thailand drives on the left side of the road.
Most drivers are well mannered and polite (up to a certain level). You will hardly ever hear a car honking and anger is rarely displayed. Despite this, traffic is rather hectic in and around busy Bangkok where calm driving is not really appreciated. Allowing a vehicle to 'cut-in' to a queue of traffic is seen as generous.
On many rural roads or even in Bangkok's small alleys, you will find motorcycles, cars and occasionally large trucks manoeuvring against (one way) traffic. This situation is complicated by the fact that many of Bangkok's roads change their one-way direction at certain hours of the day and by the fact that every new governor of Bangkok has a new traffic plan to solve the city's traffic jams. Every such plan involves changing the flow of traffic, which causes one way roads to suddenly run in the opposite directions or the number of lanes being reduced from, in extreme cases, eight to one. Regular roads may become bus lanes overnight, which then cause thousands of drivers to exit from the incorrect ramps on the expressway, thus clogging up traffic worse than before. Usually this lasts for a few months, after which the government changes or they governor realizes that the problems cannot be solved and then things go back to normal. Several computer traffic control systems have been tested or even installed, but none of them seem to resolve the situation. It has been whispered that the local traffic constables are very uncooperative when it comes to these systems that could make their employment obsolete. Some companies may even mention the word "sabotage" when asked about the failure of their traffic control system.
Driving around Thailand's country side at night is considered to be extremely hazardous, especially on holidays and long weekends. Drunk driving in Thailand is being addressed but the situation is far from safe. Many cars have broken, or no lights at all and public buses like to race one another through steep hills and around dangerous curves, supposedly just to stay awake. Low wages, too many daytime checkpoints and very tight schedules for truck/bus drivers guarantee that all of the main roads and highways have 24 hour rescue teams on standby and that most of those need to head out to accidents every single night.
It was just a few years ago when it was possible to purchase a driving license without passing any test whatsoever and a lot of the licensed drivers from that period have failed to gain sufficient experience to drive safely and are still out there...