Difference between an S corporation and a LLC
An LLC is an entity type like a partnership or a sole-proprietorship. An S-Corp is similar to the LLC as a pass-through entity, and has specific employment tax benefits. LLC's are more flexible, and may elect to be taxed as an S-Corp. In your specific case, it's always recommended to consult an accountant with your business plans.
You can research each entity's details through our learning center, which has an efficient detailed article titled 'Choosing Business Entity' that I believe you will find very helpful.
Additionally, you can also view a table of the major points between the different entities by clicking the article 'LLC vs. Corporation'.