Salt based nicotine is a type of nicotine that has a reduced PH level, resulting in less irritation as compared to traditional nicotine. This allows you to be able to vape higher strengths and avoid that harsh throat hit you get from higher strength traditional nicotine.
This type of nicotine is geared towards current, heavy smokers, as it is able to reach the bloodstream more efficiently as compared to traditional nicotine, resulting in immediate satisfaction. Don't overdo it though! Because of the high strengths salt based nicotine eliquids come in, you can easily become overwhelmed. Smaller, low powered devices such as pod systems are recommended.