Cambodians mainly speak Khmer, which, unlike other languages in the area, lacks tonality but compensates with a diverse set of consonant and vowel clusters. Young Cambodians choose to study English as a second language, and you may find individuals in large towns and cities who speak anything from basic to excellent English. Most Cambodians will know enough English to conduct a simple transaction at a tourist market, but many sellers carry calculators into which they enter figures and show you the screen to indicate the price.
A few educated elderly people can also speak French, a holdover from the colonial era when it was used as a language of instruction in schools. Because the Khmer Rouge targeted everyone who could speak a foreign language for extermination, seeing someone proficient in French outside of Phnom Penh is extremely uncommon. German and other European languages may be found in tourist areas (though they are less common than French), and Japanese is also a popular language among tourism sector employees. Nonetheless, if you do not speak Khmer, English is by far your best option.
In Phnom Penh, Chinese dialects, Thai, and Vietnamese are spoken. Thai is more common in the northwestern provinces, whereas Vietnamese is more common in the southern regions.