A startup aims to upset the market with an unprecedented way of providing a product that will become popular and replace the old way of doing business by creating irreversible change. Startups need the seed funds and have more than one founder. They require a very long time to generate profits.
On the other hand, small businesses do not need massive seed funds to start, they can generate profits right away, and they usually have one owner who is also the founder. Small businesses do not create new markets for themselves; instead, they work in an existing market and profit from it by being local.
Startups are tech-savvy companies that can scale up and proliferated by reaching all geographical areas, while small businesses are generally local businesses that do not have strong growth potential.