HTML(5) – How to use code and pre, and cite, q and blockquote tags

code for marking computer code,

pre for preformatted text.

Combined you can have preformatted code,

 …

Do not make code pre-formatted via CSS.
cite is for the title of a work only! It’s not about a source or quote, it’s only the works title (movie title, book title, etc).
q is for a short, inline quotation, so you don’t have to use quotation marks.
blockquote on the other hand let’s you quote a block of text.
Also, HTML5 does not have acronym anymore. Only use abbr now.