Population: Roughly 14,000,000 and rapidly expanding
Government: One of the most corrupt in the world. Virtually a failed state. Officially, there are regular elections, but political freedoms are minimal. Political discussion is highly suppressed. Basic services are completely lacking.
Climate: Most of the country is hot all year round. Slightly cooler during the dry season from December to the beginning of March.
Language: Khmer, English widely spoken in tourist areas, some French
When to go: High season lasts from December to March, when the weather is a bit cooler and the rains have stopped. April is ungodly hot. Arguably, the best time to be in Cambodia is late October and November. The weather is cooler, the rains are less frequent, but still quite refreshing, and the ganja harvest is in. There are also fewer tourists and the prices for hotels drop.
Visas: $20 for tourist visa on arrival, $25 for business visa. Border officials are dirty, corrupt bastards, and will often try to charge much more, but if you smile with them, are respectful, and refuse to be intimidated by their threats, you can pay only the standard fee. Visa renewal is unlimited. You don’t ever have to leave Cambodia if you don’t want to!