Hi. Instead of trying to memorize variations, I'm going to memorize the general ideas behind an opening. Do you guys know where to get the information though? Is it in certain books that deal with that, or can you find it free online? Thanks.

Depends on the opening. In some cases, there's information online, but usually, you'll need a book. Are there specific openings you're interested in, or do you want recommendations of openings that have easy to understand ideas with sources explaining them?

--Fromper

I play over a whole bunch of master games as a rule. Sometimes video lectures can be a real help too. Books work too I suppose, but I'm not that into books and they cost me.

Chess Opening Essentials Vol. 1, 2, & 3
New In Chess Series. Not MCO, ECO but rather the Ideas behind the Openings.
According to the authors, the books will never be out of date. But 70 years ago Reuben Fine could have said the same thing.
The Ideas Behind the Openings by Fine. Dated but gives you the ideas, and why of the moves.
Note that some websites have pulled the ebook as the book is under copyright. A newer Alegbraic version is available from Amazon.com.
Also see
Znosko-Borovsky, E.A. How to play the opening in chess. Dover. Descriptive, dated but good.
ON THE WEB:
General Openings-
Exeter Chess Club: Chess Openings
Basic ideas behind most chess openings
How to Win in the Chess Openings - Google Book Search
Chess Openings@Everything2.com
French Defence:
Chess Openings: Introduction to the French Defense - Associated Content
Opening Rules:
Exeter Chess Club: Chess Openings Handouts
Chess and Chess960 Wiki - chess opening

Thanks for the replies. I plan on doing the Najdorf Sicilian as black against 1. e4. Against 1. d4, I plan on the King's Indian Defense. As white, I'm going to play the Ruy Lopez. Against the Sicilian, I'm going to play the Alapin.

In other words, you're going to play the most theoretically-critical openings there are?

That's a bad idea.

Before studying the ideas behind specific openings, you need to understand how to think strategically. Silman's "How to Reassess Your Chess" is, in my opinion, the best book at teaching this stuff. This book helps you figure out the ideas inherent in any position you find yourself playing.

THEN you go and play through a bunch of master games in your chosen opening, because you're starting to have the tools to understand what the masters are doing.

But, really, Najdorf sicilian, KID, Ruy?

Those are not beginner, or even early-intermediate openings.

Kind of ironic that the most theory-laden openings are the ones that the OP is interested in. But I can see where you're coming from. Instead of sifting through all of the theory for each opening, you will look for the ideas behind the opening, play what you believe is best, and then look up why your choice worked or didn't work.

In which case, I second the recommendation of Ronaldinho's and get How to Reasses Your Chess. From taking advantage of either side of a bishop vs. knight, to initiative vs. material and how to combat an opponent with the two bishops, RYC is a one-stop shop for improving your middlegame play and minor piece endgames.

Also, look around on Chess Videos TV - The Largest Chess Video Site on the Web! and see if there are any videos there on the openings you mentioned. I have had a good experience with that site in the past, and all of their videos are free to view.

I think the most important thing is to understand the *theme* of each opening, and the general *theme* of almost all openings. Grab the center, look for mistakes from the other side, and develop ALL your pieces and castle quickly, in most cases. Here are a couple articles that touch on the subject:

Chess 101: Surviving the Opening - Associated Content

Chess 101: Learning a New Opening - Associated Content

Reuben Fine's book on the opening should give you the basic idea behind many of the openings.
However, be aware that more theoretic openings do not necessarily have "themes" to them. The higher in the theory you get, the more it comes down to concrete analysis and whether or not a move sequence "works" or not. Heavily played lines tend to splinter into separate variations where the themes of one strand may have nothing to do with the themes of another strand. That is the price you pay for playing those kinds of openings.

There are "thematic" openings, but they tend to be the ones that are considered less ambitious. I play a thematic opening on White [Colle-Zukertort] and highly analyzed openings on Black[Najdorf + Semislav].

If you are interested in the Queen's Gambit opening systems [Slav, Semi-Slav, and Orthodox] I very highly recommend Matthew Sadler's books on those openings. He spends a great deal of time trying to describe what makes those openings tick.

I wanted to adopt the KID myself, but when I've tried to play it, I get crushed. The idea behind that particular defense is that you allow your opponent a lot of space for his pawn center and then attack it from the flanks, which sounds great in theory, but is pretty tricky in practice.

My advice is to stick to classical openings for a while before you try to play anything "hypermodern."