The Rules of Spanish Spelling

In Spanish the letter z can change to c: the plural of voz is voces. The letters j and g interchange in a similar way, but the rules aren't the same. When is the letter u silent in the spellings qu and gu? When are the letters b and v pronounced like English b, and when like v? Which Spanish words have silent h? When are pronouns joined onto verbs? Why is there an acute accent on llamó but not on dio? Why do words like como and mi occur both with and without the acute accent? This short book answers all these questions and many more with a minimum of technical jargon.