I'm a hobbyist chess player and usually play online. While I've seen thousands of great chess games and win a fair bit of games online, the one thing that I have been challenged with is studying openings. Simply put, there's just so many of them and each of them has so many variations. And to add to that, every out-of-book move my opponent makes, throws me off and I don't know how to continue so it turns out to be some hybrid/weird opening (or perhaps its a real opening with a name that I just don't know about)
I guess my question would be:
What's a good way to learn some of the common/easy openings? Is it just memorize or understanding the principles for instance, what that particular opening is looking to achieve
How do I identify which of the variations to look at for a particular opening, there are often so many.
What's a good strategy to deal with my opponent suddenly going out of book or playing a novelty in an opening that I've memorized?