English conversation (英会話）is a conversation held in English. English is the language most spoken world-wide and this is used officially in many situations. For example, united nations use English as one of the official languages. This is the reason why so many people are trying to learn English and English conversation.
Contries which use English
Of course UK is one of them. This is so obvious. But in England or in the UK there are so many dialect. England, Ireland, Scotland, and Wales they all have their own dialect. Sometimes they can't even communicate with each other if they try not to speak standard English.
The USA is another conrty in which English is predominant. However they don't actually have the "official" language. So there have been a huge discussion whather or not English should be the own language taught in schools. It has been especially the case in states like California where there are a lot of immigrants, especially Hipanic people.
Canada and Australia
These country use English as their main language but French is widely used in Canada as well. Both conutries have huge population of immigrants. Especially there are a lot of Chinese immigrants and you can hear Chinese in a lot of urban cities in these countries. In Canada, Toronto is the biggest city and there are more than 150 languages spoken in Toronto. Only about the half of its residents speak English as their first language. This is interesting given that Toronto is not that well known a city in the world, but it is probably the most multi cultual, multi lingual city in the world.
New Zealand English
New Zealand is a small country but they do speak English. Their accent is distinct and a lot of people do have trouble understand them. However, like Australian English, it is old cockney English of London England and in some parts of England they do speak like New zealanders.