The idea of removing the defender in Chess is simple: an important piece or square is defended by a piece, the defender. Removing the defender gives you the ability to take the important piece or occupy the important square.
There are few ideas that are simpler than this: one enemy piece protects something, you capture the enemy piece, and that something becomes unprotected.
I will test your understanding of this concept with a few puzzles. For this quiz and the next ones, keep the “Removing the defender” idea in mind.
The setup can be more complex and you can combine the idea of removing the defender with other threats, like a fork, a pin or a discovered attack. Look at the following example combining this idea with a skewer.
It is common to combine several tactical patterns together to get an advantage. As you progress with your understanding of Chess, your tactical combinations will become more and more complex. Your first shots will be simple forks. Then you will start playing elaborate tactics combining several different ideas, like the last one.
Conclusion
Removing the defender may seem trivial: if an important square or piece is controlled by the opponent, you can simply exchange the protecting piece. Yet this pattern does not always come naturally to mind. It is nevertheless a very useful and simple tactic to win material, used in many top level games. Do not overlook it !