Fully automatic- hold down the trigger and multiple bullets are fired.
Semi automatic- trigger must be pulled each time to fire, one bullet at a time.
The term assault rifle is mostly used by the anti gun lobby. As stated above, the AR 15 used in FL operates no differently than the sidearm carried by every police officer. They are just bigger and may have better accuracy. But they operate the same.
You can purchase a semi automatic handgun that is more powerful than an AR 15. (E.g. a 44 caliber Desert Eagle) .
I agree there is no need for a large capacity mag, but to ban AR15 bec they are an assault rifle is misleading and intellectually dishonest