 A fundamental phonological division of English varieties depends upon a difference in the phonotactic distribution of the consonant R. In accents with a high degree of roticity, the R is often overtly realized in a wide variety of phonetic contexts, including post-vocalic environments such as farm or far. In the accents that exhibit a low degree of roticity, R is not used in most post-vocalic environments, thus we get both farm and far without a post-vocalic R. Mostly the varieties of English are classified as non-rotic for example RP or rotic for example standard American English. However even in the so-called non-rotic varieties there are contexts in connected speech where the R can optionally be inserted. Such effects are referred to as liaison. So it seems reasonable to define degrees of roticity rather than using a binary distinction of rotic versus non-rotic.