Please refer to this page about "conjunctive adverb": http://www.chompchomp.com/terms/conjunctiveadverb.htm
and this about "subordinating conjunction": http://chompchomp.com/terms/subordinateconjunction.htm
I wouldn't advise you to memorize them. For me, the best way to determine them is to know and understand their function.
Let's take for example the word "after." As used in a sentence with another word or other words, it is neither just a preposition nor an adverb nor a conjunction. It depends on how it is used or how it functions when used in a sentence. To illustrate this advice, please see below:
As preposition: after eating, after today, after work
As adverb: graduated the year after, see you after
As conjunction: after she left, after I had eaten, after I attended the meeting