Seed funding is the first official equity funding stage. It typically represents the first official money that a business venture or enterprise raises. Some companies never extend beyond seed funding into Series A rounds or beyond. You can think of the "seed" funding as part of an analogy for planting a tree. This early financial support is ideally the "seed" which will help to grow the business. Given enough revenue and a successful business strategy, as well as the perseverance and dedication of investors, the company will hopefully eventually grow into a "tree."
Seed funding helps a company to finance its first steps, including things like market research and product development. With seed funding, a company has assistance in determining what its final products will be and who its target demographic is. Seed funding is used to employ a founding team to complete these tasks.
There are many potential investors in a seed funding situation: founders, friends, family, incubators, venture capital companies and more. One of the most common types of investors participating in seed funding is a so-called "angel investor." Angel investors tend to appreciate riskier ventures (such as startups with little by way of a proven track record so far) and expect an equity stake in the company in exchange for their investment. While seed funding rounds vary significantly in terms of the amount of capital they generate for a new company, it's not uncommon for these rounds to produce anywhere from $10,000 up to $2 million for the startup in question.
For some startups, a seed funding round is all that the founders feel is necessary in order to successfully get their company off the ground; these companies may never engage in a Series A round of funding. Most companies raising seed funding are valued at somewhere between $3 million and $6 million.