Like diapers, there are the disposable ones and the cloth (washable) ones. I think most people use the disposable ones. In fact, in the initial days of breastfeeding, most people leak so much unless you have enough cloth ones to wash and change all the time, it is better to use disposables. After a few months of breastfeeding, things settle down and breasts are not so leaky, it is possible to just use cloth pads.
The only exception, which I found out when I have my 2nd baby, is if you use cloth breast pads with a fleece layer. This fleece layer basically keeps the moisture from seeping to your bra. It like using disposable, except you have to wash. Considering the amount of money you are going to spend on disposables, you may want to consider using this type of cloth breast pads.
I made my own cloth breast pads using flannel and fleece and I didn’t have to use a single disposable breast pad when I have my 2nd baby. Although it is amateurishly sewn, they lasted me well for months! I actually made so much I have a lot to spare. If you are interested to learn how to sew them yourself, check out Sew Your Own Breastpads.
For disposables, some comes with a sticky tape for you to attach the pad onto your bra. Some don’t so they tend to shift around. As a start, buy small amount of each brand, one brand at a time, to try out and see which brand suits you best.
What I use :
Pigeon. But only for the 1st baby, when I had not discovered the beauty of washable cloth breast pads with fleece layer. The Pigeon breast pad is thin and contoured. Crumbles up easily but all in all, suits me better than the other brands. Some of the other brands are thick and show up under the bra and top.