When I first got serious about working out my focus was on building muscle - hypertrophy. This is pretty typical for us dudes unfortunately. Nowadays I focus on performance and long term health. I view hypertrophy as more of a side benefit. In the muscle bound world of bodybuilding there is endless debate about how you make those suckers grow.
Why so much debate? Well, it's because most people don't understand that there is more than one way to get the job done. There are actually three different mechanisms whereby protein synthesis is stimulated - three different avenues to build muscle.
Mechanical tension refers to the load applied. Simply put, lifting heavy shit (1 to 5 reps) will build muscle. Muscular damage refers to inducing micro tears in the muscle fibers. Spending more time under tension will drive muscular damage. This means lifting lighter weight for more reps (8 to 15). It also means little tricks like drop sets, forced reps, and negatives. Bodybuilders refer to these as intensity techniques.
Most experienced lifters understand the first two mechanisms, but they will often overlook the third. Metabolic stress refers to applying a high cardiovascular demand on the body. Good examples of this are sprinting, high intensity interval training (HIIT), and Crossfit WOD's. Here you are stressing your body's energy delivery system which will also stimulate muscle growth.
There you go. Now, instead of getting sucked into endless debate with bro types, you can just go out and incorporate these mechanisms into your regimen. Any of them will work, but you'll maximize your results if you incorporate all three.