If you are a chess player who is looking for a defence to 1 d4, consider the ideas in this book. The book is up-to-date, with plenty of annotated recent games as examples.
The book covers the lines resulting from 1 d4 d5 2 c4 c6. Quite often, White continues with 3 Nf3 Nf6 4 Nc3. And, in this introductory book, Flear explains how to play either side of the major lines which follow:
4...dxc4 is the Slav.
4...e6 is the Semi-Slav
4...a6 is the Chameleon, a waiting move that is considered part of the Slav
In some cases, White plays 3 Nc3 Nf6 4 e3. Black can now reply 4...g6, the Schlechter, which the author also has a chapter on.
But there is a line which I think is a nuisance for Black. White can simply play 3 cxd5, the Exchange Variation. Black has to recapture, and the game becomes relatively easy for White. As the book shows, Black is not in serious trouble in this line, but I certainly would rather have White.
There is a way, however, to pretty much avoid the Exchange Variation. As Flear shows, Black can play the Triangle. That's the move order I recommend. Black plays 1 d4 d5 2 c4 e6. After 3 Nf3 Nf6 4 Nc3 c6, Black is playing a Semi-Slav and has avoided the Exchange Variation. White can still take the pawn on move 3, but it isn't as good a line.
Most likely, White will play 3 Nc3. Now, Black plays 3...c6, blocking her Queen Bishop even more. This is the characteristic position of the Triangle. White's main choices are:
4 e3, after which Black has a choice: play 4...Nf6 and get to a Semi-Slav in which White's most dangerous move, Bg5, has been avoided. Or play 4...f5, transposing to a very playable version of the Dutch Stonewall (although White can still play 5 g4).
4 Nf3, after which Black can play 4...Nf6 and get into a Semi-Slav in which White does indeed have the option of playing 5 Bg5. Or play dxc4, the Noteboom, which is wild but okay for Black.
4 e4, the dangerous Marshall Gambit. This typically goes: 1 d4 d5 2 c4 e6 3 Nc3 c6 4 e4 dxe4 5 Nxe4 Bb4 6 Bd2 Qxd4 7 Bxb4 Qxe4+ 8 Be2. White's idea is to allow 8...Qxg2, answering with 9 Qd6 Nd7 10 0-0-0 and an extremely dangerous attack. So Black tends to play 8...Na6. If you are going to play this line in tournaments, I think you'll need to study more than just this introductory book, however.
Of course, that is not all Black has to learn. As I said, there is that variation where White plays 1 d4 d5 2 c4 e6 3 Nf3 Nf6 (you do not want to play 3...c6 here, after which White has too many good options) 4 Nc3 e6. This is the Semi-Slav, which the book spends over 100 pages on. White generally plays:
5 Bg5. This gives Black the choice of playing what Flear recommends, 5...dxc4 (the Botvinnik variation). Or trying the move I use, 5...h6 (the Moscow variation). Both require some work to learn, and Flear teaches us quite a bit about both moves.
5 e3, which leads either to the Meran variation or some Meran-avoiding sideline. The Meran variation the book recommends for Black is 5 e3 Nbd7 6 Bd3 dxc4 7 Bxc4 b5 8 Bd3 Bb7, a popular line which I've used for many years.
This book is useful and easy to read. I recommend it.