Even if we did answer this question it would not help you. This is abut general knowledge (and a little about opinion). If we answered your question and you used it, your prospective employer would then probably come back with other questions either challenging your response, or simply delving the depth of your own knowledge. So, if we gave you this answer, it would only be the start of your problems, and probably making your interview worse. Simply tell what you know/think, even if you think it won't sound good enough. It's better than trying to "cheat" your way through.