I too am wondering the HM definitions. Big/small business versus startup. What is the definition of startup? I don't understand why businesses that go for VC funds have the monopoly on the term "startup".
The definition I've seen given by PG is anything that scales up. In other words, a business that sells a product that can be used by many users. A small business is usually something that offers a service (a restraunt, a barber shop, or a consulting firm).
I would say any business with fewer than 50 employees is a small business. According to Wikipedia, 37signals has 16. There are technical definitions in various countries of "small business", based in some cases on number of employees and in some case on revenues or other economic metrics. Any way you slice it, 37signals is a small business.
