Whoever controls the table controls the rally. It's one of the oldest maxims in table tennis. This usually means playing close to the table with quicker shots than your opponent, forcing him to back off, and thereby both playing more defensively and having more table to play. The Chinese dominated with this from the 1960s until the 1990s, often with blocking and quick-hitting. Then the game changed as loopers began to dominate, often controlling play from a couple steps back.
But then a strange thing happened - history repeated. Loopers began playing closer and closer to the table, and they began to (mostly) dominate against those who backed off. It's an ongoing battle, but in general, players who play quicker shots closer to the table have an advantage over those who back up.
How do you develop such close-to-table play? One of the best drills for this is the simple forehand-backhand drill. Have your opponent block side to side (or feed multiball), and you simply go side to side, attacking as quickly as you can. Most shots should be top of the bounce, but you might start taking some even on the rise, especially on the backhand. The quicker you do this in the drill - consistently - the better you'll develop the habit for use in games. One interesting thing - I found this to be the perfect drill with a lefty player (I'm a righty), since both players can play crosscourt forehands into their practice partner's backhand, while the partner practices quick side-to-side backhand blocking. For me, this was perhaps the most important drill that led to my improvement during my early years.