(a) Subscriptions to magazines that are sold for a semiannual or longer period and are entered as second class mail are exempted from the taxes imposed by this chapter.
(b) “Magazine” means a publication that is usually paperbacked and sometimes illustrated, that appears at a regular interval, and that contains stories, articles, and essays by various writers and advertisements. “Magazine” does not mean the publication of current information which is taxable pursuant to § 151.0038 of this code as an “information service.”