The currency of Vancouver is the Canadian Dollar, which is different from the American Dollar. There are currency exchanges all over the city, and most will offer a reasonable exchange rate; if you're new to the city though, head to Robson Street, where there's a high concentration of Bureau de Changes generally offering a reasonable rate.
English is the main language spoken in Vancouver. Whilst French is spoken in other parts of Canada, it isn't widely spoken in Vancouver. Other languages include Cantonese, Chinese, Mandarin and Punjabi .
Vancouver as a whole is a very safe city, but Downtowns Eastside is generally regarded as the most dangerous part of the city because of its high levels of drug use, prostitution and the high rates of violent crime.
Dial +1 for Canada, then 604 for Vancouver
Visas are not generally required for British Citizens visiting Canada for short periods.