Vanguard was established in 1975 by Jack Bogle, who believed that a mutual fund company should not have outside owners. Instead, shareholders of the Vanguard Group own the company's different funds. Thus, the shareholders are the actual owners of Vanguard.
Blackrock started in 1988 with eight people in a single room who shared a determination to put clients' needs first. By 1999, Blackrock rapidly grew to $165 billion in assets under management and then went public on the New York Stock Exchange. Over the years, Blackrock has acquired several other companies, such as Merrill Lynch Investment Management (2006) and Barclay Global Investors (2009).
All three are similar though there are subtle differences. So for the remainder of this post, as we discuss Vanguard vs. Blackrock funds, we'll refer to each interchangeably.
An index fund is a type of mutual fund or ETF, though the unique aspect always matches the components of an index or specific financial market. Index funds represent a theoretical segment of the market and aim to match the risk and reward of a specific need.
An exchange-traded fund (ETF) typically matches an index similar to index investing. However, an ETF can trade on an exchange, one of the most significant differences between an ETF and an index fund.