Canadian raising

The Canadian raising or Scottish raising is a type of pronunciation in certain dialects of English. For example, Scottish English and Canadian English. In these cases, the "ai" dipthong and "ou" dipthong is pronounced "higher" with the tongue than in other varieties of English. 
The raising of the "ai" dipthong makes it similar to "oi". The raising of the "ou" dipthong makes it similar to "oo" or "oa".