20, 30 years ago, by far the most common tackling style was for a defender to wrap up the ball carrier and drag him to the ground.
In the last 10 years, glancing tackles have become a lot more common. The kind where they just hit the ball carrier with no attempt to wrap their arms around him.
Why is this? What's the advantage and disadvantage to this type of tackle, and why has it become more prominent in the NFL?