There are three distinct approaches to the pronunciation of “z” and “c”. In most of Spain, particularly Castile, the “th” sound is used and this is distinguished clearly from the “s” sound. So, casa is “cassa” and caza is “catha”. The second option is called ceceo (pronounced “the-thayo”), in which they are both pronounced “catha”. This double-lisp is only found in southern parts of Andalusia and is considered extremely bumpkinish. The final option is seseo (pronounced “sesayo”), in which both the words are pronounced “cassa”. Non-Spanish language groups like the Basques and Catalans tend to use this option and it is the pronunciation on the Canaries and throughout Latin America.