Source and extent of funding
Angels typically invest their own funds, unlike venture capitalists, who manage the pooled money of others in a professionally-managed fund. Although typically reflecting the investment judgment of an individual, the actual entity that provides the funding may be a trust, business, limited liability company, investment fund, etc. The Harvard report by William R. Kerr, Josh Lerner, and Antoinette Schoar tables evidence that angel-funded startup companies are less likely to fail than companies that rely on other forms of initial financing.

Angel capital fills the gap in start-up financing between "friends and family" (sometimes humorously given the acronym FFF, which stands for "friends, family and fools") who provide seed funding, and venture capital. Although it is usually difficult to raise more than a few hundred thousand dollars from friends and family, most traditional venture capital funds are usually not able to consider investments under US$1–2 million.