Pullups and curls are popular exercises at both commercial and home gyms. Both exercises can be performed with minimal equipment and they both work the biceps muscle, the front of the upper arm. This is where the similarities end. To know which exercise is better, you must first define your goal.
To perform a pullup, you hang from a bar and pull your body weight up, usually until your chin reaches the height of the bar. Perform a curl by holding weight in both hands and curling the weight up to shoulder level. A pullup is a compound exercise -- it involves two or more joint movements. A curl is an isolation exercise -- it involves only one joint movement.
The exercises serve different purposes. Pullups target the back muscles, the latissimus dorsi. The biceps muscles act as synergists, they assist the back muscles in executing the movement. Other muscles involved in performing a pullup include the teres major, rhomboids and the trapezius muscle. The purpose of a curl exercise is to target the biceps muscles. The biceps are the primary movers during a curl. Other muscles help stabilize the body during the movement, but they do not actively contract.
Each exercise requires minimal, but specific equipment. To perform a pullup, you need a sturdy bar or pullup assembly. The bar must be strong enough to hold your body weight. For a curl, you can use dumbbells or a barbell.
Both exercises feature several variations. Place a chair under a pullup bar for assisted pullups. Place your feet on the chair and push with your legs to assist you in performing the exercise. Change your grip to hit your muscles from different angles. Take a close grip, wide grip, reverse grip or even a neutral grip. For curls, you can work both arms together using a barbell, or work each one individually with dumbbells. Turn your hands so your palms face each other and perform hammer curls. Rest the back of your upper arms on a pad to do preacher curls. There is almost an unlimited number of curl variations.
Neither exercise is inherently better than the other. For general fitness, a pullup works your back and biceps muscles together, saving precious time. For bodybuilders and other fitness professionals, the need to sculpt each individual muscle makes isolation exercises such as curls a mandatory part of each workout.