What is safety stock and is it necessary?

I understand the concept of inventory, but what exactly is safety stock? Is it stock that I carry or that my supplier carries?|||the term "safety stock" is just another way of saying i have extra inventory "in case i need it" - call it what you want, its extra inventory and dollars - so the best way to approach that is get your vendor to hold the "safety stock" in his warehouse for you - or better yet get him to consign inventory to you -


he puts inventory in your shop based on a forecasted usage you provide - at the end of each month you report your usage - he then invoices you for the amount used and you pay 30 days later