These light bulbs are very different from incadescant bulbs.
Incadescant buld work off of 120v current. The electricity flows through the filament. The filament has a high resistance and there for heats up and glows, just like the element on an electric stove or in a toaster.
Flourescant bulbs, regardless if it is normal output, very high output, power compacts, T5's or even metal halides all need higher voltages to make them work. In simple terms these bulbs have no filament. Thery are filled with a gas. This gases electrons are "excited" by electrical current and glows. The electrical current be of a high enough voltage to accomplish this.
If you are using incandescant bulbs you do not need a ballast. If you are using flourescant bulbs of any type they will not work without a ballast.
Brian