As any homebrewer will tell you, sanitation is the most important part of the brewing process.
We have two big sellers - Star San (acid based) and Io-Star (iodine based). The biggest difference between the two is that Star San will not stain your equipment as iodine tends to do, and it also degrades into a yeast nutrient which helps your beer. For those reasons, we recommend Star San to a new brewer. Both will keep infection away from your brew and will make for a successful brew day!
Remember, sanitize anything that comes in contact with your beer. You can never be too clean, so when in doubt - sanitize!