A push-up is the most effective basic exercise that most people tend to forget about. Incorporating push-ups into your training routine is extremely beneficial, especially if you want to build serious strength and stability in your upper body. Push-ups target several muscle groups defining your arms, chest, back, and abs.
There are almost an infinite number of ways that you could do a push-up. Using different hand placements and shifting your body weight will target different muscle groups of your torso for upper body conditioning. Best of all, push-ups are scaleable to your fitness level, so no matter what, they will always be challenging.
There are several ways to incorporate push-ups into your workouts. You could do them as a warm up exercise or as a superset burnout exercise. You could also alternate some bench press days by doing a variety of different push-ups. Regularly practicing push-ups will help build stronger pound for pound strength.
Lastly, the most important thing to remember is that its not about how many push ups you can do, its about how well can you do them.