Stability Ball (Swiss Ball)

Any exercise that you would normally do on a bench can be done on the stability ball. You can do exercises like bench press, dumbbell flyes, shoulder press, lateral raises, pullovers, crunches, reverse crunches, etc... This is an excellent piece of equipment. The ball can move and roll so it increases your balance and strengthens the small stabilizer muscles. 

Abdominal Bench

This is basically just a decline bench that is used for doing abdominal exercises. It has rollers that you hook your feet into so you do not slide off the bench. 

Preacher Bench

This bench is designed for working the biceps. It has an angled pad that you you're your upper arms on. This pad prevents you from swinging the weight so you can isolate the bicep muscles. 

Hyper Extension Bench

This bench is used for working the lower back, hamstring, and glute muscles. Some gyms have a hyper extension bench that can also be used for sit ups to work the abdominals. 

Benches

The most common piece of equipment in any gym is the bench. There are three types of benches - flat, incline, and decline. Some benches are adjustable (i.e. they can be adjusted to either flat, incline, or decline). Some benches have racks on one end for holding a barbell, while other benches do not have any racks. The benches that do not have any racks are generally used for dumbbell exercises. 

EZ Curl Bar

The EZ curl bar is designed for working the biceps and triceps. It is a shorter then a barbell and has angled hand placements. This is good for working the muscles from different angles and reducing the stress that a straight barbell can place on the wrists. 

Dumbbells

A dumbbell is a short barbell, usually 10 - 15 inches long. Dumbbell exercises are performed with a dumbbell in each hand. Most gyms have a dumbbell rack that has an assortment of fixed weight dumbbells. They usually have dumbbells from 5 lbs. - 100+ lbs. in increments of 5 lbs. (i.e. 5 lb. dumbbells, 10 lb. dumbbells, 15 lb. dumbbells, etc...). 

There are also adjustable dumbbells that have small collars that clip on the ends of the dumbbells to hold the weight plates. While they are not a convenient as a rack of fixed weight dumbbells, they are much cheaper and take up less space. They are ideal for a home gym setting.