In inorganic chemistry, when is the suffix **meta** used? (as in **metaborate** and **metasulphite**) What about the terms **pyro** and **ortho** (as in **orthophosphorous acid**)? For example, I recently came to know about the prefixes **per** and **hypo** which are used to refer to the highest and lowest oxidation states of an element respectively (like **perchlorate** and **hypochlorite**). Are there any terms and conventions I should be aware of?